The Red Devils face Champions League-chasing Everton at Old Trafford on Sunday before a Champions League last-16 clash with Real Madrid.
And the Scot says he must place his full trust in his players in order to ensure he has fresh legs in both games.
|A DOUBLE TREBLE
|40/1||Manchester United are 40/1 to win the Premier League, FA Cup and Champions League with Bet365|
“I trust the squad of players I have. They are all internationals, they are all good players and there is no reason why I can’t play them.
“They’re all contributing in their own way and that gives us a better chance of dealing with the various competitions we’re in.”
The United manager also lamented the fact that preparations have been disrupted by midweek international friendlies, adding: “There is not a domestic manager who can agree to friendly internationals at this time of year."
However, he did concede that the confidence boost provided by England's 2-1 win over Brazil could help two members of his squad.
“I was happy for Wayne Rooney and Chris Smalling to play full games at Wembley because they have not had a lot of football anyway," he concluded.