Saints keeper Mannus - "Rosenborg took us lightly" - Latest - The Scotsman ST Johnstone goalkeeper Alan Mannus claims cocky Rosenborg paid the price for failing to take their Europa League clash seriously enough. Read David Ferguson's match report from McDiarmid Park Tommy Wright's side last night completed a famous 2-1 aggregate win over the Norwegian league leaders to send them spinning out at just the second qualifying round. But Mannus believes the former Champions League quarter-finalists - whose wage bill is 18 times Wright's £1million budget - failed to show Saints enough respect after they stunned them with a 1-0 win in Trondheim. Rosenborg striker Nicki Nielsen admitted he was surprised by how good the Scots were after the first leg while boss Per Joar Hansen insisted his team were still the better equipped to progress. Stevie May, however, ensured St Johnstone claimed a major scalp when his equaliser confirmed a 1-1 draw in the McDiarmid Park return. And Mannus, whose side will now take on FC Minsk of Belarus in the third qualifying round, told Press Association Sport: "Their budget is so much bigger than ours but for a team that was supposed to be in the Champions League a few years ago, I think they underestimated us. They were a bit arrogant with some of the things I heard that they had said. I don't read the papers but some of the boys in the changing room told me what had been said. Rosenborg thought it was going to be a case of turning up and winning. They thought they were so much better and I don't think they even came to watch us play. That shows a certain level of arrogance if that was the case and it has backfired on them. May has spent the last year and a half out on loan with first Alloa and then Hamilton but has been recalled to Perth by new Saints boss Wright. And his faith in the 20-year-old striker was repaid immediately with the crucial leveller that cancelled out Alexander Soderlund's fourth-minute strike for the visitors. Mannus now expects to see big things from the Perth-born frontman. "I was talking to Steve Banks earlier this summer when he first came into the club and I asked him if he had seen Stevie," said Mannus. He said he hadn't but I told him he will score goals for us this season. I've seen him in training and he can strike the ball the way Cristiano Ronaldo does so that it moves all over the place. He's not the type of guy to get fazed by big games and he showed that against Rosenborg and the way he took his goal. It was a very calm finish after nicking in between the goalkeeper and defender. St Johnstone's average attendance was just 3,640 last term but 7,850 turned out to cheer them on to victory last night and Mannus is hopeful the newcomers will return. He said: "Beating Rosenborg was a huge result for the club and the city of Perth as well. You saw by the size of the crowd how important it was to them and it made a difference to us as a team. Hopefully they can keep turning out because the atmosphere was unbelievable. St Johnstone - whose opening Scottish Premiership fixtures with Hearts and Kilmarnock have both been pushed back by 24 hours to accommodate their next Europa League tie - survived a late bombardment to see off their opponents. Mannus was required to make two crucial blocks in final 20 minutes to add to a string of saves in Trondheim. But the shot-stopper admitted a broken scoreboard left him fretting in the closing stages. "There's no time up on the board so you have no idea how long is left," he explained. "At one point I thought to myself: "We must be in the last 10 minutes now." When the referee came over I had a look at his watch and it said there was another 20 minutes to go. That wasn't what I wanted to see and it seemed to be a really long second half. I was hoping that we could keep hold of the ball but Rosenborg seemed to win it back a lot and were punting it forward. But we defended brilliantly, especially in those closing minutes and we deserved to go through.