Zlatan Ibrahimovic's desire to win is insatiable, according to Marouane Fellaini, who says the Manchester United striker wants to win every game, even in training.
Ibrahimovic instantly became a favourite with the Old Trafford faithful with five goals in as many games at the start of the season and, although a slump followed, his return of 20 in 33 appearances is a handsome one in his first season in England.
The former Barcelona, Inter and Paris Saint-Germain striker sows the seeds for his exploits on the practice pitches at United's Carrington training base and, even at 35 years old, Fellaini reports he is a relentless presence on a daily basis.
"He is always there to train, shouting, he wants to win," the Belgium midfielder told The Telegraph.
"We play 10 against 10 and he's there shouting. He wants to win the game and he will do everything to win the game, even in training.
"There are big characters at the club, but they are good guys and that is most important.
"They know when they have to talk after the game, before the game, when they have to give confidence. Big characters but very good guys."
United head into Saturday's home match with Watford aiming to extend a 15-match unbeaten run in the Premier League - a far cry from the chastening 3-1 loss at Vicarage Road earlier this season that left Mourinho livid.
"Of course the manager was angry,” Fellaini said. "We had the meetings, he showed us the mistakes and what we did wrong.
"It's normal. Since the beginning of the season, we have had a lot of meetings like that. It shows his character and how he wants the team to play.
"Now the manager has worked with the team since July, so he knows us better. As well, the players know each other and the understanding is better."
Fellaini has struggled to enjoy the kind of rapport with United's supporters as he did with the Everton faithful since moving to Old Trafford in 2013, becoming synonymous with David Moyes' ill-fated reign.
He was booed after conceding a penalty that allowed his former club to claim a 1-1 draw with United in December but insists the ordeal gave him "more motivation to do better".
Despite the presence of world-record signing Paul Pogba, the 29-year-old remains an important part of United's squad and revealed Mourinho offered assurances to this end before the start of the season.
"Jose called me and texted me on my holiday to give me confidence and say he trusts me," said Fellaini, who is now contracted to United until the end of next season after the club triggered a one-year extension clause last month.
"When a manager calls you and says you are part of his plans and that he trusts you, then you will give everything for him."