The 23-year-old, who joined Mourinho’s side from Borussia Dortmund in May 2011, made just four appearances in La Liga as Real Madrid were crowned Spanish champions last term.
Sahin, capped 31 times by Turkey, has been linked with a move away from the Bernabéu this summer, with Arsenal among the clubs understood to be keen to sign the midfielder.
Mourinho said: “The point is, he’s a young boy, he wants to play every match. He wants to be happy to play, he wants to play to be happy.
“And in Real Madrid with Xabi Alonso, with [Sami] Khedira, with Lassana [Diarra], [Esteban] Granero, [Mesut] Ozil, the situation is not easy.”
He added: “Real Madrid is very difficult. It is not an easy club, because we demand a lot. We have great players, and when you don’t start well, it is difficult to do it.
“If he stays, he’s not a problem for me, he’s one more solution.
“We leave [the situation] in his hands. Be happy. Decide what you want to decide, to be happy.
“If you decide to leave we are going to help you to leave. If you decide to stay, we are going to support you and try to succeed this season.”
• A former teacher, Mourinho had spells working at Sporting Lisbon, Porto and Barcelona as a coaching assistant in the 1990s.
• As coach, he had a brief, nine-game stay at Benfica and a highly successful tenure at Leiria before really making his mark after his arrival at Porto in January 2002. In his first full season, 2002/03, Porto won the Uefa Cup and a domestic double. The next year they retained their league title and claimed the Champions League with a 3-0 victory over Monaco.
• He joined Chelsea in 2004 and led the club to the League Cup and their first league championship for 50 years in his first season. Followed up with the league title again in 2006, and both the League Cup and FA Cup in 2007.
• Mourinho left Chelsea in September 2007 and stayed out of football until joining Inter in June 2008. In his first campaign the Nerazzurri retained their Serie A crown, a feat they repeated in 2009/10 when they also added the Coppa Italia and the Champions League crown, their first European Cup win since 1965.
• Victory at the Santiago Bernabéu was Mourinho’s last act as Inter coach before joining Madrid on a four-year deal. His first season featured the club’s first Copa del Rey victory in 18 years and a Champions League semi-final appearance.
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