The Pool Two leaders clinched a quarter-final place thanks to tries in the last three minutes of a pulsating encounter from fly-half David Holwell and lock Malcolm O’Kelly.

Leinster led comfortably during the first-half, but then trailed 20-13 after 1998 European champions Bath rekindled memories of their Heineken Cup glory days by fighting back magnificently.

The Irish outfit though, despite winning barely 25% of second-half possession, struck in dramatic fashion as Holwell charged down a kick to score before mercurial centre Brian O’Driscoll sparked the last-gasp attack from which O’Kelly ultimately prospered.

Holwell finished with 17 points, and there was also an early try by flanker Shane Jennings, while Bath scored tries through lock Steve Borthwick and wing Brendon Daniel. Olly Barkley kicked two penalties and two conversions – but crucially missed two straightforward second-half penalty attempts – and fly-half Chris Malone dropped a goal.

Bath’s quarter-final ambitions ended amid amazing late scenes, but Leinster should be confirmed as top seeds for the knockout stages if they beat Italian champions Treviso in Dublin next weekend.

The severity of Bath’s injury crisis was emphatically underlined before kick-off, as they could only name one back among their replacements – scrum-half rookie Mike Baxter.

Coach John Connolly was also forced to draft in 19-year-old hooker Dave Ward, with skipper Jonathan Humphreys sidelined, and prop Matt Stevens provided hooking cover on the bench.

In contrast, Leinster paraded a galaxy of international stars, spearheaded by O’Driscoll, O’Kelly and hooker Shane Byrne as they targeted a fifth successive group victory.

Bath needed to start confidently, but they suffered a nightmare opening, gifting their opponents a try inside two minutes.

Ward’s lineout throw drifted over his intended target – England forward Grewcock – and before Bath could regroup, Jennings pounced on possession and showed great strength by barging over through two attempted tackles.

Holwell added the conversion, before booting an angled penalty after Malone opened Bath’s account by landing a drop-goal from 45 metres.

Leinster though, maintained their stranglehold and almost went further ahead when some sublime approach work from O’Driscoll cut open Bath’s midfield defence.

His delicate pass freed midfield partner Gordon D’Arcy, before O’Driscoll featured again in a thrilling move, but full-back Girvan Dempsey dropped the ball just two metres from Bath’s line.

It was a huge let-off for the home side, who struggled to cope with Leinster’s fluency, so Bath captain Steve Borthwick sensibly switched to forward power after Holwell kicked his second penalty.

And the impact was immediate as Bath slashed their deficit when the pack drove relentlessly from a close-range lineout, enabling Borthwick to touch down.

Barkley converted and then kicked a penalty, hauling Bath level following a 10-point scoring burst in four minutes that stunned Leinster.

Holwell missed a penalty with the final kick of an exciting first-half, but justice was done after he gained the opportunity when team-mate Eric Miller took a dive in open play, an act that resulted in Bath prop Duncan Bell being harshly sin-binned by French referee Joel Jutge.

Bath’s Joe Maddock was replaced at half-time, and a paucity of backs on the bench meant that flanker James Scaysbrook replaced him, with Michael Lipman moving from back-row to right-wing.

Bath dominated the early second-half exchanges, despite Bell’s temporary absence, and they should have gone ahead, but Barkley inexplicably rifled a 20-metre penalty attempt wide.

Leinster, having cruised through the opening quarter, were ruffled by Bath’s stirring and prolonged riposte from 13-3 down, and the home forwards continued battering away before gaining their reward on 59 minutes.

Leinster absorbed relentless pressure deep inside their own 22, yet they had to crack eventually, and Bath worked enough space for Daniel to score wide out, with Barkley kicking an angled conversion.

The visitors’ 1,000-strong travelling band of supporters could hardly believe their team’s startling demise, and Leinster, from a position of such early strength, found themselves completely outgunned.

Barkley botched another penalty chance 13 minutes from time before finding his range after Bell had been helped off injured, taking Bath 10 points clear and within touching distance of a famous win.

The drama continued though, courtesy of Holwell charging down Malone’s attempted clearance, converting his own try and then adding the extras to O’Kelly’s clincher, concluding a classic encounter.