Jesse Lingard has revealed that playing under caretaker manager Ole Gunnar Solskjaer at Manchester United is "not all jokes and smiles."

Solskjaer has overseen the Red Devils' significant upturn in form since succeeding Jose Mourinho in mid-December, with the Norwegian masterminding a run of five wins from five matches.

Mourinho's tenure ended in acrimony, and one of the key changes in the United side under the perennially upbeat Solskjaer has been a huge improvement in the mood at the club.

However, speaking ahead of Sunday's Premier League clash with Tottenham Hotspur at Wembley Stadium, Lingard said the former United forward is not afraid to lay down the law, per Sky Sports:

"He has got a hairdryer in him. He will put his foot down and tell you how it is. That is what you need sometimes if a game is going well, you need a pick-me-up to remind yourself that you are a Man Utd player and you play with pride and passion.

"It's not all jokes and smiles. We work hard and that's what he wants. He wants 100 per cent from each player and everybody to know their job on game day. We are clued up through the week on what we need to do."

Lingard added that it now "feels like the old [United]" at the club, as Mike Phelan, Sir Alex Ferguson's long-time No. 2, is back in the coaching setup.

Phelan was jettisoned from the United coaching staff soon after Ferguson's retirement in 2013, when David Moyes opted to bring in his own people.

Solskjaer brought him back to the club when he was appointed as caretaker manager and referenced the impact of his absence after his opening game in charge, a 5-1 win at Cardiff City:

Sunday's meeting with Spurs will be the biggest test of Solskjaer's United tenure so far.

Comfortable league wins against Huddersfield Town, Bournemouth and Newcastle United followed the thrashing of Cardiff, but those are all games United would have been expected to win—even under Mourinho.

Spurs are still in the title race, and they beat United 3-0 in the reverse fixture at Old Trafford back in August.

If the Red Devils lose by an equally emphatic scoreline at Wembley, it will be a major reality check and evidence they still have some way to go before returning to the upper echelons of English football.

If United win, though, it will be another feather in Solskjaer's cap and a further step of progress as they look to break into the top four.

Mourinho was sacked with United 11 points off the UEFA Champions League spots in the Premier League.

That gap will shrink to six if United beat Spurs, and Solskjaer's side will also be tied on points with fifth-place Arsenal.