Harlequins outscored Clermont four tries to two and produced a fine display, yet it still was not enough to reach the European Challenge Cup final as the hosts won 32-27 at the Stade Marcel Michelin.
Clermont will face fellow French side La Rochelle in the final in Newcastle on May 10, but Gustard was not too downbeat as he turned his attention to the Premiership play-off race.
“The boys are sitting in the changing room hurting that we didn’t win. We did enough in the game to win and outscored Clermont four tries to two,” he said.
“They average six tries a game in this competition. We scored a maul try against them and that doesn’t happen often.
“We’re disappointed, but we have an opportunity in the league now. We have to take the positives from this game.”
Harlequins turned around 18 points down, with first-half converted Clermont tries coming from Fritz Lee and Damian Penaud while Camille Lopez kicked two drop goals and Morgan Parra added a couple of penalties.
Gustard said: “I asked the players to come here and win. We caused Clermont problems in the first half and they respected our defence.
“They got two tries from nothing. It was missed tackles. Our set-piece and particularly the line-out didn’t function and that was the story of the first half. We lost too much ball and couldn’t sustain pressure on them.
“We felt like we were in the hunt and our game changers made a big impact. I think Semi Kunatani had his best game for the club.
“We tried to run the ball from deep and we made line breaks from that. Marcus Smith was one of them and I was pleased with his game management. I thought it was one of the best performances I’ve seen from a young fly-half.”
Clermont eventually edged the contest and they still have not lost at home this season.
Their replacement scrum-half Greig Laidlaw said: “It’s brilliant. It was all about winning tonight and it wasn’t too pretty at the end.
“In the middle part of the game we were pretty good, but then we just shut up shop and stopped playing a little bit.
“If you give a team like Harlequins time and space they are going to hurry you. Credit to them, but we scored more points and we’re in the final.
“It will be a good final with two big French teams going at it. We’ve had some good tussles with them already this season.
“Both teams will be going there to win, only one team can, and hopefully if we get our stuff right on the day it can be us.”
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