Leo Cullen praised Leinster's application after the defending champions swept aside Toulouse in a 30-12 Heineken Champions Cup semi-final win at the Aviva Stadium.

James Lowe, Luke McGrath and Scott Fardy all touched down and fit-again captain Jonathan Sexton kicked 12 points as the province advanced to face 2017 winners Saracens in a mouth-watering May 11 decider at St James' Park in Newcastle.

"Probably what pleased me most is the attitude of the players over the course of the last couple of weeks and how they applied themselves in training," said head coach Cullen.

"When they prepare well, they've a much better chance of performing well in these big games. There was great fight for each other. You could see the players, how much it means to them.

"I think the fight to stay in the battle is really important from our guys. I think they showed a lot of resilience, particularly as they (Toulouse) got close to our try-line. They're good qualities to have in these big games."

While the returning fly-half Sexton was the official man of the match, the title holders had a number of star performers as they restricted Toulouse to just three penalty goals from Thomas Ramos and one from replacement Romain Ntamack.

Chief among them was London Irish-bound flanker Sean O'Brien, whose return to fitness in recent months has coincided with long-term injuries to Josh Van Der Flier and Dan Leavy.

"Seanie is an unbelievable competitor. He's worked incredibly hard to get back from his injury. You can see what it means to Seanie the way he plays," said Cullen.

"I thought he was really exceptional today. It's not just his performance, it's how he leads the group.

"In the week, the way he talks. How he understands the threats the opposition pose, both sides of the ball. In terms of dominating that contact area, he's one of the best players to have ever played the game, certainly Irish guys.

"I think he's showing again what he's capable of. It was good to have Seanie back out there."

Meanwhile, despite the obvious frustration at losing to Leinster in such comprehensive fashion, Toulouse skipper Jerome Kaino was doing his best to remain upbeat.

With a place in the Top 14 Championship's knock-out stages already assured, the former New Zealand international believes they need to take the positives from their European adventure, which showed they are a resurgent force.

"I think our young group can take a lot of experience from that game," he said. "It's disappointing we couldn't get the result, but I think we still have another challenge ahead of us in the Top 14.

"We'll take a lot of experience, a lot of positives, from our European Cup campaign.

"I think they (Leinster) were able to build on their momentum. We defended well at times, but we weren't able to build on our momentum when we did get forward."