Rooney arrived at Old Trafford in 2004, in exchange for £27M. He has since become captain, won the Premier League five times and the Champions League in 2008, and smashed United's all-time goalscoring record.
The striker's contract ends in 2019. However, since Mourinho arrived in June 2016, Rooney has made just nine Premier League starts. This has led to speculation and many clubs showing interest.
He was targeted earlier in the year by big-spending Chinese clubs, such as Guangzhou Evergrande, Beijing Guoan and Jiangsu Suning, but nothing came of that.
Now, the latest club to show interest is West Ham, who have plans to spend big in the Summer, and are looking for a right-back and a striker.
A senior source at the club confirmed that they would try to sign Rooney. When asked upon the likeliness of the England captain's signing, the source said: "Never say never"