Jimmy O'Brien scored four tries as Leinster marched on in the European Champions Cup with a ten-try demolition of Bath.

Josh van der Flier, Jordan Larmour, Ciaran Frawley, Andrew Porter, Hugo Keenan and Dan Sheehan also crossed as the four-time European champions finished their Pool A fixtures with 15 points and a points difference of +136 – despite forfeiting their second game in Montpellier 28-0 due to Covid issues.

Leinster fielded eight of the Ireland starters who toppled the All Blacks, including captain Johnny Sexton, but Bath began brightly.

The hosts forced four penalties in the first five minutes which prompted Italian referee Andrea Piardi to issue a warning to Sexton. Bath opted for lineouts each time and failed to register any points.

Already without 20 of their squad through injury or Covid isolation, Bath lost Sam Underhill after only 15 minutes after his head seemed to collide with Robbie Henshaw’s hip. The England flanker had only just returned to action after a similar injury against Gloucester on St Stephen's Day.

Josh van der Flier is congratulated after scoring

The spell was broken by a dangerous Leinster break-out and O’Brien’s touchdown was ruled out when the TMO spotted Jordan Larmour holding back Max Clark as the ball ricocheted over the tryline.

The left wing was not long denied however, crossing for a 16th-minute try from Henshaw’s pass as Bath’s defence was left exposed.

Sexton’s conversion attempt struck the post but he made no mistake after Josh van der Flier picked an exquisite line past Will Stuart and rounded Orlando Bailey after 25 minutes.

Bath’s woes were underlined when flanker Tom Ellis kicked the ball through a scrum and Leinster’s big forwards sucked in defenders before Larmour cut through to add a third try. Sexton converted for a 19-0 lead.

Although centre Clark followed up a galloping run by skipper Charlie Ewels to get Bath on the scoreboard, with Bailey adding the conversion, Leinster went up another gear to lead 33-7 at half-time with further converted tries by O’Brien and replacement Ciaran Frawley.

There was no letting up after the break as Leinster took full advantage of Bath’s right wing Gabriel Hamer-Webb being sin-binned for a deliberate knock-on.

Robbie Henshaw is tackled by Will Stuart and Will Spencer

Three tries followed in just six minutes. Ireland loosehead prop Andrew Porter first grounded the ball from close range before O'Brien celebrated his hat-trick from Sexton’s crossfield kick and the immaculate Hugo Keenan brought up 50 points from a quicksilver counter-attack.

Leinster were also reduced to 14 when replacement Max Deegan clumsily tackled Ben Spencer off the ball. Bath roused themselves to apply serious pressure but lacked the poise to earn any points.

All too predictably, when the visitors went back on to the attack, replacement hooker Dan Sheehan burst through midfield to add a ninth try and there was still time for left wing O’Brien to chase down his four-timer. Ross Byrne converted both to add to Sexton’s five successful kicks.