Ulster are back in business after gaining revenge over Leinster with a 26-13 win at a packed Ravenhill.

It means that the 1999 European Cup champions leapfrog over Leinster in the race for one of the two Heineken Cup places for next season.

Last week they went to Dublin, where defeat by Leinster looked to put them out of the running. But they came storming back with a brilliant performance which only went into dimmed a little at the start of the second half.

It leaves Ulster now on 10 points, one ahead of Leinster with Munster looking certain to stretch their lead at the top on Saturday afternoon in Galway against Connacht.

Ulster skipper David Humphreys was the man pulling the strings, in a pulsating game that kept the 10,000 crowd happy.

The home side could not have wished for a better start. Keeping the ball in the hands, they enticed Leinster to stray off-side and Humphreys slotted over an angled penalty after three minutes.

Ulster continued to set the pace and a superb break by flanker Russell Nelson set up their opening try. The South African-born blindside with Irish qualifications sprinted 20 metres before firing out a long pass to Ryan Constable out on the left wing. Although tracked down, Ulster recycled the ball and right wing James Topping danced his way through under the posts for Humphreys to convert.

Leinster had a quick reposte with Brian O'Driscoll dropping an opportunist goal from close-in. O'Driscoll picked up an ankle injury soon afterwards and had to receive lengthy treatment before continuing.

But it was Ulster again who took command with Nelson making the initial surge deep into Leinster territory after good inter-play between backs and forwards. Nelson off-loaded to Andy Ward who bounced off Liam Cullen and Gordon D'Arcy, and brushed aside Girvan Dempsey's half-hearted tackle to sprint 22 metres to the line. Humphreys converted from wide out to edge his side 17-3 ahead, a deserved gap which they held until half-time.

Leinster clawed back the leeway after only 90 seconds of the restart. O'Driscoll was put into space by Nathan Turner, and although Denis Hickie was caught just short of the line, his pack kept possession until Ulster's defence was nowhere as fly-half Mark McHugh scrambled over for a try under the posts which he converted himself.

Leinster were throwing everything at Ulster in the third quarter and only desperate defence kept their line intact.

Ulster finally broke the siege when they entered Leinster territory on the hour and Humphreys slotted over his second penalty. Then after Ulster hooker Ritchie Weir had charged down a Brian O'Meara clearance, Leinster were
penalised 30 metres out and Humphreys did the needful again.

McHugh, who was not having a good day with the boot up until the 67th minute, stroked over a penalty after missing three previous attempts to leave Ulster 23-13 ahead.

Ulster sniffed the victory they badly needed to boost their Heineken Cup hopes, and stepped up their control the game in the final 10 minutes. Humphreys obliged with his third penalty as his side held out for a deserved victory.

Ulster - G Henderson; J Topping (S Stewart 75), R Constable, J Bell, T Howe; D Humphreys (capt), B Free (S Bell 63); J Fitzpatrick, R Weir, S Best; G Longwell; M Blair, R Nelson (D Topping 59), A Ward, T McWhirter

tries: J Topping, Ward; cons: Humphreys 2; pens: Humphreys 4

Leinster - G Dempsey; D Hickie, B O'Driscoll (P McKenna 74), N Turner (A Dunne 80), G D'Arcy; M McHugh, B O'Meara (S Keogh 76); R Corrigan, S Byrne (P Smyth 59), G Halpin (P Coyle 63); L Cullen (R Casey 59), M O'Kelly; T Brennan, E Miller (D O'Brien 17), L Toland (capt)

try: McHugh; con: McHugh; pen: McHugh; drop: O'Driscoll

Referee - Bertie Smith (IRFU)