Jose Mourinho expressed his concern about the potential schedule logjam facing Manchester United in the final months of the season, saying Wednesday it poses the team "many, many, many problems."
Jose Mourinho and Pep Guardiola shared a storied rivalry in La Liga with their sides Real Madrid and Barcelona.
United is still involved in four competitions — the Premier League, the FA Cup, the Europa League and the League Cup.
"If we progress in the competitions," Mourinho said, "we will be in trouble."
United is through to the last 32 of the Europa League — it plays French club Saint-Etienne in the first leg tomorrow — and has also reached the last 16 of the FA Cup.
There are 13 rounds left in the Premier League, in which United is in sixth place and fighting for Champions League qualification through a top-four finish.
And United has got through to the final of the English League Cup against Southampton on February 26.
With 13 weeks left in the season, United could have 27 games to play. Multiple games per week would be commonplace, especially since United is in good form with only one loss in 22 games in all competitions.
"We cannot choose competitions at Man United," Mourinho said.
For that reason, Mourinho is set to play a strong team against Saint-Etienne at Old Trafford, in a competition that offers the winner an automatic place in next season's Champions League.
"The Europa League is a not a competition we want to play," Mourinho said, "but we play."
Mourinho said Wayne Rooney, Michael Carrick and Phil Jones will miss the game because of injury. Paul Pogba is set to play, which will mean the France midfielder taking on his brother, Florentin, for the first time in a competitive game.
"It's a good, nice destiny," Mourinho said. "I think only mum Pogba is in trouble. It's impossible for the lady to choose. I know, from Paul, that the mum wants a draw."