Ashley Young hailed the impact of interim boss Ole Gunnar Solskjaer after a "crazy week" at Manchester United ended in a five-star show against Cardiff.

The post-Jose Mourinho era started in style as United scored five goals in a Premier League match for the first time since Sir Alex Ferguson's last game in May 2013.

"I don't think he (Solskjaer) has stopped smiling," United captain Young said after the 5-1 win in the Welsh capital.

"He was like that as a player. He always has a smile on his face and I think that can reflect down on to the team, which is a good thing.

"Ole has come in and we were preparing in the right way for a game, even though it's been a crazy week.

"There was only a couple of days from when he came in, but as professional players you go out to train and want to turn the loss against Liverpool into a win.

"After a performance like that I am sure he will be delighted."

Mourinho lifted the Europa League, EFL Cup and Community Shield in his first year at Old Trafford before finishing runners-up in both the league and FA Cup.

But his third season quickly unravelled as discontent over the lack of transfer summer activity led to dressing room disharmony and United falling way off the Premier League pace.

There were public fall-outs with key players such as Paul Pogba and Anthony Martial – who were both recalled by Solskjaer and impressed at Cardiff – but Young denied stories that the dressing room had celebrated Mourinho's departure.

"No celebration at all. Absolute lies," Young said.

"Obviously it was disappointing for the manager to get sacked.

"In his two-and-a-half years he won trophies. We have to take some responsibility for that (his sacking) as we are on the pitch.

"But we have to move on from that. As professional players we have to get on with the job in hand, and that is what we did here."

Solskjaer's first tasks were to release the attacking handbrake which many felt that Mourinho had applied to the side and breathe energy into the team.

The Norwegian did that on the tactical front as full-backs Young and Luke Shaw raided forward and midfielders flooded the box.

United were rewarded with goals from Marcus Rashford, Ander Herrera, Martial and Jesse Lingard (two), and also outran their opponents for the first time this season.

"Everyone had a good game. Paul was good, but every man from front to back, including the players that came on were fantastic," Young said.

"We didn't know what was going on in some games in terms of why we were not winning when we felt we should have.

"It just wasn't going our way. Now we just want to go out there, play football and win games.

"As players we have to concentrate with what happens on the pitch, not off it."

Cardiff never recovered from Rashford's early free-kick strike and the timid defeat ended a run of three straight home wins.

But the Bluebirds remain two points clear of the relegation zone and manager Neil Warnock said: "If you'd told me we'd be out of the bottom three at Christmas, I'd have snapped your hand off.

"I'm sure (Christmas opponents) Palace and Leicester will be rubbing their hands with glee at playing Cardiff City, but you never know."