United are set to play in the Europa League final against Ajax later in May, but still have Premier League matches against Southampton and Crystal Palace to play.
But while he described the situation at United as "unfortunate", Schweinsteiger told ESPN he did not believe Mourinho was exclusively responsible.
"It has been an incredibly busy season, which will see us play 64 matches including an astonishing nine matches last month".
United's 2-1 loss at Tottenham Hotspur on Sunday confirmed the club would finish outside the top four for a second straight year and the Europa League final against Ajax is now a must-win if they are to secure a Champions League spot next season.
United head to St Mary's to fulfill their penultimate fixture in the Premier League at a time, when all thoughts are directed towards next Wednesday's Europa League final.
Balancing the desire to win with resting players has been hard and Mourinho said it would have been worse it not for Oliver's decision to red card Ander Herrera sending off in the 1-0 FA Cup quarter-final defeat at Chelsea in March.
Donald Trump: Israel, Palestine leaders get on 'unbelievably well'
They said the Israeli High Court said lawyers should be allowed to visit striking prisoners. He said, "I hope that it's possible to achieve a change and to pursue a genuine peace".
"I don't know the way the other clubs think; I don't know what is important for them", Mourinho said. He did not just come in and say "there you go - play every game".
Zlatan Ibrahimovic, James Wilson and Marcos Rojo are all long-term absentees, with Timothy Fosu-Mensah and Ashley Young also out.
United, whose best known players include Paul Pogba and Wayne Rooney, said it expected to report full-year revenue between 560-570 million pounds, better than its previous forecast of between 530-540 million pounds. This is a period in one week I have to give a day off.
Mourinho has appeared unimpressed by the number of games the England trio of Smalling, Luke Shaw and Phil Jones have missed this season, repeatedly querying if some of his players have the right mental attitude.
They had been due to play each other in Beijing, China past year, but the game was called off due to concerns about the pitch.
Puel said: "The last result away against Middlesbrough allowed us the possibility to finish strong in the Premier League". United's pre-season tour of the United States also features games against the LA Galaxy, Real Salt Lake, Barcelona and Real Madrid.
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