Fly-half Ryan Lamb is primed and ready for two weekends of "knockout rugby" as Gloucester enter a critical stage of their season.

Only victory over Cardiff Blues in Sunday's Heineken Cup Pool Six clash at Kingsholm will be good enough for Gloucester, who go into the match trailing the Welsh side by four points.

If Gloucester can beat the Blues, they will then head to Biarritz five days later still in with a chance of reaching the last eight for the second successive season.

But No 10 Lamb and his team-mates are well aware that defeat at Kingsholm this weekend will render their trip to Parc des Sports Aguilera meaningless as they will be at least six points adrift of David Young's men and highly unlikely to qualify as one of the best pool runners-up.

"This is a massive game for us as a club," said Lamb, who came off the bench in last weekend's wind-affected 10-7 defeat at Newcastle but will start at Kingsholm on Sunday.

"We got out there last week and it was just ridiculous – Newcastle didn't do a lot, we didn't do a lot and it was a dead game.

"But it's a different mindset for us this week, especially as it's knockout rugby for us going into these last two pool games.

"If we lose this week, I think we're out, so it's important for us to go out there and prove we can compete at the high end."

Gloucester were beaten 37-24 on their trip to the Millennium Stadium in October as the Blues' gamble on switching the match from the 13,000-capacity Arms Park paid off.

Young's men capitalised on some sloppy play from Gloucester to score four tries and bank a bonus point which could yet prove crucial in determining who tops the pool.

But Lamb says that defeat has not dented his side's confidence ahead of the return fixture this weekend.

"We thought we were maybe the better team down there, especially in the first 30 minutes, but they got two quick tries and made us play a bit of catch-up," said Lamb.

"It was a bad result for us, especially with them getting the bonus point, but we know what we are capable of if we stick to our game-plan and we are confident we can come away with the win."

And while a bonus point would help make up for the one they shipped in the Welsh capital three months ago, simply winning the match is Gloucester's initial priority.

"In an ideal world, we'll go out and score 50 points and get a bonus point, but sometimes it doesn't end up like that," said Lamb. "That being said, we're going into this game full of confidence – despite what happened last week and at Cardiff.

"We've got to go out there and get the win first, but if we can get a couple of quick tries then maybe we can go for that bonus point. But you can't go out in Europe, especially against a side as good as Cardiff, saying you are going to get a bonus point."

Lamb this week retained his place in the England Saxons squad ahead of their forthcoming matches against Portugal and Ireland A, and was joined by club-mates James Simpson-Daniel, Olly Barkley and Nick Wood.

But with Gloucester facing Cardiff, Biarritz and Guinness Premiership leaders London Irish on the next three weekends, the 22-year-old is only thinking about his club for now.

"Obviously it's good to be in the Saxons squad. You'd love to be in the main squad, but there are so many good 10s around at the moment," said Lamb.

"But I just want to keep my focus on playing for Gloucester for now, because we've got a massive three weeks coming up."

Gloucester head coach Dean Ryan will name his side to face Cardiff today – and is likely to be boosted by the return of flanker Peter Buxton from an ankle injury.

Elsewhere, he has tough calls to make on Simpson-Daniel, Iain Balshaw and Olly Morgan in the back three, as well as choosing between Barkley and Anthony Allen at inside centre.

The winners of the Western Daily Press Heineken ticket competition are Bernie Trott and Martin Allen, who both correctly answered that Heineken is brewed in Holland. They will each receive a pair of tickets for Sunday's big match.