Manchester United manager Jose Mourinho says some of his players may have to play through injury. Photo: Reuters / Andrew Yates

MANCHESTER, England – Jose Mourinho has called on his tiring Manchester United stars to show resilience in the face of a daunting fixture list that will define their season.

United have nine games in April that will go a long way to deciding whether they qualify for next season's Champions League.

They can achieve that goal by finishing in the top four of the Premier League or by winning the Europa League, in which they play Belgium's Anderlecht in the quarter-finals.

But United manager Mourinho has revealed that England defenders Phil Jones and Chris Smalling, both injured in training with the national team this week, are set to be long-term absentees.

And, with record signing Paul Pogba struggling to recover from a hamstring problem, Mourinho has challenged his remaining players to step up.

"They have to be resilient, they have to be professionals," Mourinho said.

"They have to be team players, they have to go to the limits, they have to play with small injuries, they have to play with pain, play with fatigue because there is no other chance.

"When I look, for example, in two weeks we are going to play against Chelsea. Before, we play Anderlecht and after, we play Anderlecht.

"Chelsea, before they are on holidays and after they are on holidays. You can name their team, you can say 'This one, this one, this one, this one and this one'.

"In 15 days' time maybe the Premier League is not important for us, maybe it is.

"If we keep winning matches now, that match against Chelsea is an important match for us. If we lose matches now, that match is not important; then the important matches are only Anderlecht.

"They have to cope with everything like they did in that week against Rostov, coped with the bad pitch, coming from London by bus, they coped playing against Chelsea with 10 men, coped with playing against Rostov three days later.

"But some bodies they felt it. Like Pogba's body felt it and had a negative reaction. So we need to be strong and need to believe."