Liam Rosenior claimed Chelsea are "very close to being an outstanding team" despite Paris Saint-Germain's thumping win leaving the Blues on the brink of a Champions League exit.

Chelsea were thrashed 5-2 in the first leg of their last-16 tie after Khvicha Kvaratskhelia came off the bench to score twice, having also assisted Vitinha's 74th-minute finish that sent PSG 3-2 ahead on Wednesday.

Rosenior's side had twice levelled either side of half-time through Malo Gusto and Enzo Fernandez, responding to Bradley Barcola's opener and Ousmane Dembele's well-taken finish that restored PSG's lead.

And Chelsea did look good value for large parts of Wednesday's encounter at Parc des Princes, accumulating 1.53 expected goals (xG) to their hosts' 0.87.

"Even at 4-2, we were still right in it. The fifth goal, that's the painful one. It's something I have to really solve. We are very close to being an outstanding team," Rosenior said during his post-match press conference.

"I need us to maintain our calm when we have setbacks. This is on me. It's something we've spoken about since the day I came in.

"I'm not pointing the finger at the players. If we don't overcome this hurdle, we won't reach our potential, and it's my job to find the solution."

The defeat also marked only the second time Chelsea have conceded five goals in a single Champions League game, after a 5-1 defeat to Barcelona in April 2000.

Filip Jorgensen was largely helpless for the other four goals, but for Vitinha's cool lobbed finish, he ceded possession as Barcola's attempted interception fell the way of Kvaratskhelia to tee up his team-mate.

The Chelsea goalkeeper was preferred over Robert Sanchez for this clash, and Rosenior says he will continue to utilise whoever he sees as the best option.

"They have different qualities. Rob is outstanding at dealing with crosses and is an outstanding shot-stopper. Filip has amazing qualities, too," he continued.

"Players make mistakes. Filip isn't the first to make a mistake; that's part of football. Credit to him, he held his hands up in the dressing room.

"Everyone makes mistakes; sometimes they're more costly than other times, and this is one of those moments.

"One of the reasons we won at Villa was because we were so calm in possession. If you can stay calm here [vs PSG] and play through the press, we can have our moments, and we did."

Chelsea have now lost each of their last three knockout stage matches in the Champions League – their joint-longest run in the competition (also in February 2012 and August 2020).

They will need a minor miracle to overcome a three-goal deficit at Stamford Bridge next Tuesday, with Rosenior acknowledging PSG's quality.

"They're European champions. That's why I'm so disappointed because our performance up to the third goal was very good, but it can't be spoken about now because of the result," he added.