Harlequins' Mike Brown forces Toulouse's Vincent Clerc into touch during their clash at Le Stadium on Sunday © Getty Images

Enlarge

Related Links

News: Brown set for Six Nations call-up

News: Gough cited for dangerous tackle

Features: Transferring that winning feeling

Match Pack: Heroic Harlequins stun Toulouse

Match Pack: Munster see off Scarlets again

Match Pack: Northampton rip Castres asunder

Match Pack: Glasgow's Lamont stars on return

Match Pack: May strikes for Gloucester

Match Pack: Racing ruin Exiles' hopes

Match Pack: Seven-try Leinster thrash Bath

Match Pack: Tigers keep European hopes alive

Match Pack: Ulster hit Aironi for six

Match Pack: Biarritz back in business

Match Pack: Edinburgh exact Blues revenge

Match Pack: Saracens seize control with famous win

Tournaments/Tours: Heineken Cup

Teams: England | France | Ireland | Italy | Scotland | Wales

Typical. Just typical. Just as the pattern of this season's Heineken Cup appeared to have been established, the competition delivers the kind of result that reminds us that nothing is set in stone in the battle for Europe's top club prize.

Harlequins' stunning 31-24 triumph over French giants Toulouse not only breathed life into their Pool 6 campaign but also underlined the largely unpredictable and thrilling nature of the tournament. Having had their shortcomings painfully exposed by Toulouse at The Stoop the previous week, Quins were up against it in the return leg and fighting for their euro lives but they rose to that challenge in sensational style to claim a resounding victory.

Bullied on their own patch, Conor O'Shea's charges proved themselves to be quick learners and their swift reply is a ringing endorsement of the coaching team and the enviable self-belief of the squad honed during their march to the top of the Aviva Premiership. Fullback Mike Brown was at his fiery best with two tries and a try-saving tackle on Toulouse winger Vincent Clerc while fly-half Nick Evans was back to his game-bossing best a week after being knocked out of his stride by Kiwi rival Luke McAlister. The visitors may have ridden their luck with one-try and courted controversy off the field - with team manager Grahame Bowerbank and flanker Will Skinner feeling the wrath of referee Alain Rolland for playing the ball and denying the chance for a quick lineout - but make no mistake, Quins are firmly back on track.

The unexpected result at Le Stadium blew the pool wide open with Gloucester's narrow 23-19 victory over Connacht keeping their euro hopes alive. Replacement Jonny May pounced in the closing stages to deny Connacht their first win of the campaign and ensure everything is still to play for when the battle resumes next month.

Quins were not the only Premiership side to flex their muscles with Saracens bolstering their claims with a 16-13 success against the Ospreys in their Pool 5 clash in Swansea. An opportunistic score from No.8 Ernst Joubert and the boot of centre Owen Farrell helped account for a disappointing Ospreys and end their proud 17-game unbeaten streak in the competition at the Liberty Stadium.

Sarries look on course for the quarter-finals and would hope to wrap up qualification at home to Treviso in Round 6 but before then they must travel to Biarritz who survived a scare against their Italian rivals before running out winners 29-12 on Saturday. Bidding to avoid embarrassing back-to-back defeats following a shock reverse to Treviso the previous week, the hosts did just enough with late tries from forwards Wenceslas Lauret and Arnaud Heguy added a little gloss to the result.

Leicester were another side to return to winning ways with a battling 23-19 victory over Pool 4 rivals Clermont Auvergne helping to discredit those who had written the Premiership contingent off as a spent force. Denied a bonus point at the Stade Marcel Michelin the week before, the Tigers trailed at the break with Kiwi speedster Sitiveni Sivivatu having opened his Heineken Cup account but back came the hosts with a try from flanker Julien Salvi and England fly-half Toby Flood guiding the hosts home and preserving their five-year unbeaten run at home in the competition. As elsewhere, the race for top spot is far from decided with Ulster's 46-20 victor over whipping boys Aironi - their second bonus point success in as many weeks - leaving them in pole position.

Things appear a lot clearer in Pool 2 where Leinster handed Bath a lesson on their way to a thumping 52-27 victory in front of a bumper 46,365 crowd at the Aviva Stadium in Dublin. The memory of a host of missed chances in their narrow victory over the same opposition in Round 3 were cast aside in a seven-try rout led by a brace from winger Luke Fitzgerald with fly-half Jonathan Sexton once again pulling the strings. The result leaves them six points clear of second-placed Glasgow who claimed a share of the spoils with a 13-13 with Montpellier. The Scots side had recorded an impressive home victory over the French side last weekend and their latest effort keeps their slim hopes of progressing alive.

As impressive as Leinster were in despatching their latest euro foes, their Irish rivals Munster boast a more impressive record having notched their fourth successive victory with a hard-fought if not dazzling 19-13 win against the Scarlets in Limerick. Just like the previous week, the Scarlets were guilty of not making the most of their opportunities and as a result a more ruthless Munster, guided by veteran No.10 Ronan O'Gara, cemented their place at the summit of Pool 1. Elsewhere, Northampton Saints finally got their euro assault up and running - at the fourth time of asking - with a 45-0 drubbing of Castres. Fullback Ben Foden notched two of the Saints' six tries that propelled them to their first victory in the competition but it is likely to be a case of too little, too late for the Premiership side who lie third in the table and eight points adrift of the leaders.

Edinburgh are on the brink of a first quarter-final appearance for eight years having exacted revenge with a 19-12 victory over Cardiff Blues in their latest Pool 2 encounter. Tim Visser's first-half try and a 14-point kicking haul from Greig Laidlaw earned the hosts a third win from four European matches that leaves them tied with the Blues on points but ahead on try count. The result at Murrayfield leaves London Irish still in the Pool 2 mix despite their 25-19 home defeat to Racing Metro but their failure to follow up their victory in Colombes means they have a mountain to climb if they are to progress.