Inspired by Ireland's stunning displays in the autumn international series, Robbie Diack insists that there is no room for error in tonight's clash with the Scarlets.
Sitting bottom of Pool Three with just one point after suffering defeats in both of their opening games, Ulster must win at the Kingspan Stadium or their European Champions Cup dreams are over.
"We know what we're up against this week and we know we're going to have to be at our best to compete with them," said Diack.
"We had two disappointing results in the first two European games and we know the importance of winning, especially the home games."
Putting in a shift against Georgia to earn his second Ireland cap last month, the South African is feeling confident that he can emulate his strong international performance at club level. But the 29-year-old admits that successive Ireland wins have formed expectation for him at Ulster and subsequently massive pressures.
"It gives you a bit of confidence but it also adds a bit of pressure and you don't want to be part of a squad like that and then come to Ulster and then not perform as well," he said.
Coming off the Ulster bench with 20 minutes to spare in last weekend's agonising 21-20 defeat to Munster, Diack showed his strength with a number of hard tackles and he is on a mission to verify his position in both Neil Doak and Joe Schmidt's squads.
"I wanted to perform and I wanted to prove it was a good decision for me to be down in Dublin with Ireland," said Diack. "To get 20 minutes to try to contribute and do as much as I can, it was great. But at the end of the day we lost which was disappointing. We should've won."
"I just want to contribute in any form or way that I can and whether (last Friday) that was just to come off the bench and carry and give a bit of energy to the players who had been on there for 60 minutes already and had fought hard, then that's what I needed to do.
"It was just great to be back with Ulster. I'd a fantastic couple of weeks down with Ireland and it was fantastic to be involved in the Georgia game and great to be involved in a successful series, even though I wasn't part of the two big games, South Africa and Australia.
"But I was excited to get back playing for Ulster and get back to the players, around my friends, and team environment."
Despite the Scarlets shock 14-8 loss to Connacht last weekend, Diack insists that the side will not be easy opponents.
"We've had a good look at them and played them early on in the season and it was a tough game over there. It was lucky we got back and got the draw.
"They've got a huge pack and they've got a very experienced pack and a lot of them played for Wales (in their 12-6 victory) against the Springboks last weekend as well.
"To physically bully the Springboks is a huge feather in their cap,"added Diack.
But the forward believes that Ulster, with the help of his fellow Ireland team-mate Rory Best, will go onto the pitch at Kingspan well prepared to tackle the Scarlets and reignite their European chances.
"Rory is always increasing the tempo of training. That's his big emphasis - to make it short and sweet and sharp and to try to make it as error-free as possible." said Diack.
"All you want in the training sessions is for the intensity to be high and that's what they're like down in the Ireland camp - and that's what Rory is good at.
"We've trained hard and now we're just looking forward to the game. The first thing you want to do is win the game but we're going to have to be at our best."
Injured Jared Payne may be on the side-lines tonight but he hopes his team-mates come through unscathed.
"I think both Ulster and Scarlets will have had a bit of a wake-up call after last week's results so it looks like it's going to be a good game," he said.
"We're all looking forward to the game - it's going to be two teams banging it out at Kingspan but I think we'll come through okay. We just have to try to win these few next games and then see what happens."