Mauricio Pochettino said that Tottenham Hotspur's Wembley form cost them their Champions League dreams.
They lost to AS Monaco 2-1 at the Stade Louis II needing at least a draw to stay in contention for the knockout phases, but the manager said their earlier results had sunk them.
"I think we made too many mistakes at home at Wembley. We don't deserve to go through to the next round because we didn't show enough quality," Pochettino said.
They previously lost to Monaco and Bayer 04 Leverkusen at Wembley in London, where they have been playing due to renovation work at White Hart Lane.
He said they had their chances in France.
"We are out and we have time to assess and analyze," he said after the game. "It is true we feel disappointed, but today we missed opportunities."
MAURICIO: "At this level you cannot concede goals the way we did. You will always pay in this competition. We're very disappointed." pic.twitter.com/f9TwdJbloM
— Tottenham Hotspur (@SpursOfficial) November 22, 2016
He said they would need more talent in future campaigns in Europe.
“It was a good challenge for us to compete in the competition and to show our real level. That is important … but to be competitive in the Premier League and Champions League, we need to show more. Maybe we need to add more quality in the squad."
“We have quality, yes. To compete in Premier League, yes, but today you could say we struggled a little bit. When you have problems, injuries, it is difficult to be competitive."
Harry Kane, who scored an equalizer before Thomas Lemar's winner, said they needed to focus more.
"We got ourselves back in the game at 1-1 and it was schoolboy to concede straight after that," Kane said. "We had to try to grind out a win because we were not great tonight. The second goal took the stuffing out of us. I just don't think on the day we were good enough."
Monaco went ahead again when Lemar put a shot into the left corner after a run by Djibril Sidibe, who scored first.
Former 'Spurs player Glenn Hoddle said Tottenham were poor both defensively and in posession.
The former Spurs player and manager said: "There was no passion there tonight, I think there are too many players floating along there, not finding their best form."
"They have got to do something about it, they are all looking at each other instead of saying: 'I am going to be the one to change this team.'"
The only 'Spurs player to come away with credit was goalkeeper Hugo Lloris, who saved a first-half penalty and made one of the saves of the season from a Kamil Glik volley to keep the score at 2-1 in a man-of-the-match display.
Hoddle said that the number of saves the French goalkeeper makes exposes Tottenham's problems.
"We've always said how Lloris has played so well this season, it's alright getting clean sheets if you come off and think the goalie has had to make one save, but he is making save after save, now they are getting found out. You can't keep doing that for too long."
A victory or a draw against CSKA Moscow in their final Champions League game will ensure that Tottenham go into the Europa League.
“It can be frustrating we are not in the Champions League, but it is good for the club to be in the Europa League and go further in the competition," Pochettino said. "We are in a process, we need to improve. We feel bad, disappointed, but tomorrow is another day we need to look forward.”