13:00 All 24 cars get away from the grid cleanly for the formation lap.

Barrichello is also starting on hard tyres from 19th on the grid.

12:59 Schumacher had the option of which tyres to start with after he didn't set a time in Q3 yesterday and he's gone for the softs. Heidfeld is on the hards.

12:57 It'll be worth keeping an eye on Nick Heidfeld's progress this afternoon. He's starting from the back of the grid today after a fire in final practice ruled him out of qualifying. He has six sets of brand new tyres - three soft and three hard - so has plenty of options to take a different strategy.

12:55 The drivers are being strapped into their cars and the grid is starting to clear, we're just five minutes away from lights-out at the Circuit de Catalunya.

12:53 Vettel tells the BBC that his team has been working on his KERS overnight and he expects to have it working at the start of the race. He didn't sound 100% confident, however.

12:52 There's no doubt who the fans at teh circuit want to win. Chants of Alonso are ringing out.

12:46 We haven't seen any major crashes into the first corner this season. But in this morning's GP2 race there was big shunt on the run down to turn one between Jules Bianchi and Giedo van der Garde, a stark reminder of what can happen

© Sutton Images

12:42 The big question is whether Vettel's KERS has been fixed overnight. If it hasn't then he could be a sitting duck on the long run down to the first corner.

12:38 Hamilton vowed yesterday that he would try to be in the lead into the first corner, so we'll keep an eye on him as he puts pressure on the Red Bulls off the line. To be honest, if he doesn't find a way past on the first lap he probably won't see either Vettel or Webber again for the rest of the afternoon.

12:30 Welcome to ESPNF1's live commentary on the 2011 Spanish Grand Prix. The pit lane is opening as I type and 24 highly-strung V8s are being warmed up in the garages ready to hit the track and line-up on the grid. Mark Webber will start on pole position with Red Bull team-mate Sebastian Vettel alongside and Lewis Hamilton and Fernando Alonso behind in third and fourth.

Lap 1

Alonso leads the race after a superb start from fourth on the grid. The crowd is going wild as the Spaniard leads Vettel, Webber and Hamilton.

Petrov is up to fifth and Schumacher is up to sixth with a brilliant start from tenth.

Lap 2

Kobayashi is in the pits with a left rear puncture. He takes on hard tyres and heads back onto the track.

Vettel is 0.7 seconds behind Alonso but clearly much quicker. With the help of the DRS on the next lap he should be able to attack the Ferrari.

Lap 3

Button is all over Buemi for ninth place. A terrible start for the McLaren.

Lap 4

Alonso leads by 0.8 seconds, with Vettel, Webber and Hamilton close behind.

Lap 5

Button is past Buemi. He pulled off the move on the inside of turn four and then completed it into turn five.

Lap 6

Vettel is 0.6 behind Alonso across the line but the DRS hasn't yet allowed him to get past. the gap between each of the top four drivers is less than a second but we know how difficult it is to pass here. It will all come down to strategy.

Lap 7

Button and Massa are battling over eighth. The McLaren is clearly quicker and Massa is still struggling with the balance of his Ferrari.

Massa is locking up on almost every heavy braking zone which will be damaging the tyres significantly.

Lap 8

The DRS simply isn't working here as the cars are so tightly packed. So as Button activates his, Massa has his wide open as he hunts down Rosberg.

Lap 9

Perez came out of the pits following an early stop and came out straight into a fight with Liuzzi. The HRT was not willing to let the faster Sauber through and the pair nearly made contact.

Lap 10

Vettel pits from second and takes on another set of soft tyres. That indicates a four stop strategy. Vettel comes out behind Button but is on fresher tyres so should be able to attack.

The Red Bull does exactly that and passes Button into turn five and then Massa into turn 10.

Lap 11

Alonso pits, as does Webber. And crucially Alonso comes out ahead of Vettel, who was stuck in traffic, with Webber slotting back into third in that fight.

Button is now past Massa, who seems to be being overtaken in every corner.

Lap 12

Hamilton pits for brand new soft tyres. Petrov also pits and nearly takes out his jack man.

Hamilton has come out ahead of Webber and gained a place in the pit stops.

Lap 13

Alonso sets a new fastest lap to extend the gap to Vettel to 0.8 seconds. Hamilton is 0.9 seconds behind the Vettel and 2.6 ahead of Webber.

Towards the end of the lap the top three have really bunched up. We also have confirmation that Vettel is using KERS this afternoon.

Lap 14

Just 0.5 second gaps between the top three as they cross the line this time around. Webber has dropped to 2.8 seconds off Hamilton.

Button is getting ready to pit and might be able to eke out a three-stop strategy this afternoon.

Lap 15

Button comes out ahead of Petrov and behind Schumacher. Di Resta is currently sixth having not stopped but is not giving up his place to Schumacher despite having older tyres.

Lap 16

Now di Resta pits. And Button continues his progress by passing Schumacher into turn four.

The McLaren driver is getting his afternoon back on track after a bad start but has a 24 second gap to Webber.

Lap 17

Back at the front, the top three are still running line astern, with 0.6 second gaps between the drivers.

Lap 18

Button is told that he will be able to attack Webber if he looks after his tyres and makes one less stop than the front runners.

Lap 19

Vettel pits for a brand new set of soft tyres.

Lap 20

Alonso does pit but Hamilton stays out. Webber also pits.

Vettel's strategy works perfectly and Alonso comes out of the pits behind the Red Bull. Vettel nailed his outlap and passed Alonso on the undercut.

Lap 21

Hamilton is now going very quick and sets a new fastest lap. The McLaren driver could make this work for him if he can maintain his pace and match Vettel.

But Vettel is responding to Hamilton now and should come out ahead of him once the McLaren pits. Hamilton should get past Alonso in the stops, however.

Lap 22

Hamilton's pace is still good but McLaren have to be careful. If the tyres go off completely he could come out behind Webber.

Lap 23

Hamilton was slower than Alonso on that last lap, so unless he is going to three-stop he has to come in now.

Meanwhile, Webber is starting to put pressure on Alonso for position.

Lap 24

Hamilton pits and comes out ahead of Alonso and Webber. McLaren timed it just right and now Hamilton is on fresher tyres than the cars behind him and Vettel in front.

Lap 25

Vettel has a lead of 4.9 seconds after those pit stops. But he now needs to concentrate on looking after his tyres. So far he has done a ten lap stint and a nine lap stint.

Lap 26

So the big fights on track are now Alonso v Webber and Schumacher v Rosberg.

Lap 27

Schumacher pits from sixth for his second stop. Rosberg is now in clean air but he will struggle to pass his Mercedes team-mate.

Lap 28

The gap at the front is now down to 3.4 seconds, with Hamilton 0.4 seconds quicker on that last lap.

Rosberg does indeed pit on this lap but as predicted Schumacher stays in front.

Lap 29

Hamilton gets the gap down to 2.7 seconds, making use of his fresher tyres. This could get interesting.

Lap 30

Webber and Alonso pit for hard tyres and the Ferrari just stays in front. That was a straight fight between the pit crewsand they were very closely matched.

Lap 31

McLaren are ready in the pits for Button who takes on softs and can now attack Alonso and Webber in front on hard tyres.

Lap 32

Hamilton now has the gap down to 1.6 seconds.

Button told he has to do a minimum of 13 laps on his new set of soft tyres to make his three-stop strategy work. He's currently 8.2 seconds behind Alonso and Webber.

Lap 33

Vettel reacts to Hamilton to extend the gap to 2.1 seconds.

Meanwhile, Webber is all over the back of Alonso, who we know is not a fan of the hard tyres.

Lap 34

Vettel is now 1.2 seconds up on Hamilton so something must have happened to him on the last lap, either traffic or - less likely - a mistake.

Lap 35

Vettel pits and Hamilton takes the lead.

Webber beat Alonso into turn ten but Alonso reacted in turn 11 and took the place back. Great racing.

Lap 36

Hamilton reacts to Vettel with a pit stop staright away. He takes on hard tyres and comes out behind Vettel.

Button pulls a brilliant overtaking move on Webber into turn one after making use of his DRS. But the main factor there was the tyres, Button was on soft and Webber was on hard.

Lap 37

And Button is now past Alonso too. That trio all have to pit once more so Button has put himslef into a podium position.

Lap 38

Hamilton is matching Vettel's pace at the front with 2.5 seconds separating the pair.But it will be difficult for him to pass as they are now on the same strategy.

Lap 39

Webber is back on the tail of Alonso. This looks like it will be a race-long battle.

Back in ninth Alonso's Ferrari team-mate loses the rearend into turn ten and has a half spin.

Lap 40

Alonso pits for his fourth and we expect final time.

Meanwhile the battle between the Mercedes is heating up, with Schumacher blocking Rosberg into turn one.

Lap 41

Hamilton now has the gap to Vettel down to 1.5 seconds. Webber is also pushing hard to try and leapfrog Alonso at his next pit stop.

Lap 42

Alonso told to nurse his tyres as he needs to make them last 25 laps until the end of the grand prix.

Lap 43

Schumacher pits with Rosberg expected to come in on the next lap.

Back at the front, Vettel is maintaining the gap to Hamilton at around 1.2 seconds. Both still have to pit once more.

Rosberg makes his pit stop as predicted but comes out behind Schumacher, so that battle will continue until the end of the race.

Lap 44

Hamilton can see Vettel ahead but got heavily blocked by Karthikeyan's HRT.

Lap 45

The gap is now 1.8 between the front two, so that lap in traffic was very costly for Hamilton. It looks as though Vettel is not using his KERS which means if the McLaren gets close, Hamilton will have KERS and the DRS available to him down the pit straight.

Lap 46

Hamilton now has the gap down to 1.3 seconds as Vettel is struggling to find a good brake balance as a result of his KERS problem. The KERS harvests energy from the rear axle and when it isn't working it can make the car feel a bit unbalanced under braking.

Lap 47

Hamilton gets the gap down to 1.1 seconds.

Meanwhile, Webber now has enough of a gap over Alonso to make his final pit stop and come out in front. The Red Bull is 9.7 seconds off of Button who also has to stop once more.

Lap 48

Webber makes his pit stop and takes on hards. He comes out well ahead of Alonso.

Lap 49

Vettel pits for his final set of hards. A very clean stop and he comes out just ahead of Heidfeld in clear air.

Button has also made his final pit stop and comes out in third.

Lap 50

Hamilton pits too for hard tyres. He lost 0.6 seconds in the pit stop to Vettel but now they are on exactly the same tyres and in a straight fight to the finish.

Lap 51

Vettel is told he can use KERS again as he crossed the line 1.9 seconds up on Hamilton.

Kovalainen has crashed at turn four. The Lotus is in the barriers and it looks as though it was a fairly heavy impact even though we haven't seen a replay.

Lap 52

Hamilton has the gap down to 1.3 seconds with the fastest lap of the race.

Lap 53

This race isn't over yet. But Vettel is responding with his best first sector of the race so far.

Heidfeld passes Maldonado for 12th, but there are no points to be gained back there.

Lap 54

Hamilton has closed the gap again with just 1.0 second separating the top two. Vettel has KERS working but did not use all his quota on that last lap.

Lap 55

Trilli holds up Vettel in turn five and Hamilton is now on the Red Bull's gearbox and within range to use his DRS.

Lap 56

It's very close into turn one but Vettel moves to the inside line to block Hamilton. The McLaren used KERS and the DRS to try and get close but it wasn't quite enough.

Lap 57

Hamilton is told he can use extra revs and fuel if he wants.

Lap 58

Hamilton is too far back again on this lap. He needs to get a tiny bit closer through the final corner but that is easier said than done.

Lap 59

Hamilton was closer on this lap but still not quite close enough. We've got seven laps remaining.

Perez passes Massa for eighth with ease thanks to his soft tyre advantage over Massa's hards. Heidfled also gets past the Ferrari as Massa continues to struggle for grip.

Heidfleld is now all over the back of Perez but they are both on soft tyres.

Lap 60

Massa runs wide and into retirement at turn 10. He's been struggling all afternoon and appears to have called it a day.

Lap 61

Alonso is also struggling with his tyres but Ferrari are reluctant to pit him. He would come out ahead of Schumacher 26 seconds behind.

Lap 62

Hamilton has the gap at 0.7 seconds but appears to be dropping off the pace. Having said that he's still got the Red Bull in his sights on the pit straight.

Lap 63

Hamilton tends to be matching Vettel in sector one, losing time in sector two but then gaining a bit back with the DRS down the pit straight.

Lap 64

Vettel does not have KERS again so the McLaren has a straight-line speed advantage while the Red Bull is faster in the corners.

Lap 65

Hamilton got closer through sector three on that last lap but then Vettel also got the use of the DRS thanks to a back marker. The next lap will be Hamilton's last chance.

Lap 66

Vettel celebrates with his father and team as Hamilton and Button share stories before heading to the podium. Vettel looks as ecstatic as he has been at any race this season.

Vettel wins by 0.6 seconds ahead of Hamilton after a brilliant final few laps.

Button crosses the line 35 seconds behind Hamilton and on a three-stop strategy. Webber takes fourth after starting on pole and Alonso takes fifth.

Schumacher held team-mate Rosberg off for sixth. Heidfeld was eighth with Perez and Kobayashi rounding out the points positions.

Vettel gets the benefit of a backmarker again on the final lap and holds off Hamilton for the final time into turn one. A brilliant race by these two, but it looks like Vettel is going to come out on top.

Thank you for joining us for a brilliant Spanish Grand Prix. Make sure you keep checking the website this afternoon for all the reaction from the teams and drivers.

The German and Austrian national anthems ring out for the fourth time this season followed by the customary champagne spraying.