Bath staged a rousing second-half fightback to keep their Parker Pen Challenge Cup hopes alive in a physical semi-final first-leg clash at the Recreation Ground.

The Zurich Premiership leaders trailed their opponents until the 72nd minute with prop David Attoub's second-half dismissal for collecting two yellow cards sparking their revival.

With Montferrand's pack weakened, Bath cranked up the pressure and were rewarded with touchdowns from England fly-half Olly Barkley, Wylie Human and Andy Beattie while referee David McHugh also blew for a penalty try.

The win gives John Connolly's side a fine chance in the second leg at the Parc des Sports Marcel-Michelin but whether their 14-point advantage will be enough when they face Montferrand on their own patch is another matter.

The French club have only a slim chance of making their domestic play-offs but are a powerful side packed full of internationals and the Parker Pen Challenge Cup is realistically their only route into the Heineken Cup next season.

France centre Tony Marsh was outstanding throughout, his ferocious tackling denying Bath any passage through the midfield, while the pack dominated until Attoub's exit in the 49th minute.

It was a full-blooded encounter which saw four yellow cards and erupted into violence in the first half, but Bath gave as good as they got and deserved to finish convincing winners.

Barkley, who finished with 14 points, overcame a shaky start to orchestrate play to good effect at fly-half while full-back Matt Perry looked comfortable after overcoming his injury problems.

Bath saw plenty of the ball in the opening 10 minutes but were let down by some poor decision-making from Barkley and indiscipline in their opponents' 22 which saw two promising field positions ruined by needless penalties.

They threatened briefly through Andrew Higgins and Human but both breaks were snuffed out by an impressive Montferrand defence led by Marsh.

Marsh's international team-mate Aurelien Rougerie went desperately close after Olivier Magne's 40-yard dash had swept the visitors deep into enemy territory, but Barkley made a crunching try-saving tackle which hurled the winger into touch.

Montferrand could not be denied for long though as they ran in two tries in three minutes, stretching Bath's defence to breaking point with some quickfire rucking for the first which was concluded when Gerald Merceron strolled home.

Magne added the second after intercepting Martyn Wood's pass at a line-out and outstripping three opponents in a chase for the line. Anthony Floch landed the conversion to give his side an unexpected 12-0 lead.

Human was denied five metres short of the line when Perry's kick bounced unkindly with a try there for the taking but there was some reward for Bath as in the subsequent breakdown Marc Reynaud was shown a yellow card.

Isaac Feaunati and Attoub followed Reynaud into the sin bin on the stroke of half-time following a lengthy dust-up but referee McHugh could have dispatched at least another two as several players were involved.

One was former England hooker Richard Cockerill who was then involved in a bizarre incident which saw him punched by his Montferrand team-mate Brent Moyle when tempers had cooled and McHugh was consulting the touch judge over what action to take.

Barkley slashed the deficit with a penalty but three points from Floch saw Montferrand wrestle back the initiative, until Attoub was sent off after being shown his second yellow card for excessive use of the feet.

Bath looked to make the numerical advantage tell immediately and their efforts were swiftly rewarded in the 55th minute when Feaunati burst through the middle before the ball was recycled and fed to Barkley who scampered through.

Human crossed seven minutes later following some excellent work from Perry, who tricked his way through Montferrand's defence, but the try still took some finishing and Human did well to plant the ball over the line.

A penalty try followed after Montferrand had collapsed a string of scrums while in the dying moments Andy Beattie barged his way over with help from his pack to complete the comeback.