Glasgow Warriors head coach Franco Smith said he was frustrated his side did not score from a late driving lineout against Harlequins - but backed the decision not to take three points.
With the score poised at 24-21 in the visitors' favour, Glasgow won two kickable penalties inside the final 10 minutes. Rather than kick the three points, they went to their lineout, which had earlier yielded a try for Johnny Matthews.
Smith said he was disappointed with the execution of the play, but backed the decision.
He said: "We should have converted the last two penalties when we went for touch in the corner.
READ MORE: Five things we learned as Glasgow fall to dramatic Harlequins defeat
"If you look at the way champions win big games - [teams like] Leinster and La Rochelle - they take the big opportunities, and we need to do that.
"The score was 24-21 at that stage, so if we take the three there, it becomes a six-point lead. If they then score a try, they win by one point, so nothing changes. We had two opportunities to score the try that would have made it 31-21.
"I’m not regretting those decisions, but we are kicking ourselves for not using those opportunities."
Smith, who guided Glasgow to the Challenge Cup final last season only to lose that match to Toulon, praised his team for their performance after trailing 21-7 at the break.
"To come here and perform that way, the character we showed to come back into the game, it’s fantastic," he said.
The South African added: "We should have won the game through the way we produced that character, and that’s the growth of this team.
"The Champions Cup is a massive competition with Test match-like rugby. There has definitely been progression. You can’t compare the final of the Challenge Cup with what we have achieved here."
Meanwhile, ex-Glasgow Warriors boss Danny Wilson was delighted to get one over his former side.
Wilson was sacked by Glasgow in 2022 after a humiliating URC play-off defeat to Leinster.
READ MORE: Danny Wilson opens up on time as Glasgow Warriors head coach
Earlier this week, he downplayed facing his former team for the first time, but after guiding Harlequins to a first-ever Champions Cup knockout win, said he was delighted to have beaten his former employers.
Speaking to broadcasters TNT post-match, Wilson said: "I'd love to stand here and say it's not about that, but it is. To win a knockout game is pleasing, but to do it against Glasgow is even more pleasing.
"I knew against Glasgow with their form and the way they're playing would be really tough."
Harlequins will now play the winner of Saturday's round of 16 tie between Bordeaux-Begles and Saracens in the quarter-finals back at The Stoop next weekend.
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