MANCHESTER, England -- Luke Shaw is yet to make a firm decision about his future at Manchester United and will assess his options this summer, sources have told ESPN FC.
Shaw was fully fit for West Bromwich Albion's visit to Old Trafford on Sunday but was left out of the 18-man squad by manager Jose Mourinho.
The left-back was also omitted from the matchday squad for the victory over Manchester City at the Etihad Stadium.
He has not featured since being substituted at half-time during the 2-0 win over Brighton in the fifth round of the FA Cup on March 17.
Sources have told ESPN FC that Shaw's continued struggle to win over Mourinho will prompt the defender to consider his future at the end of the season, although he has not ruled out staying.
United have triggered a one-year extension in his contract that could keep him at the club until 2019.
Mourinho suggested in February that Shaw, 22, would sign a longer deal, but sources have told ESPN FC that is yet to materialise.
Shaw, signed from Southampton for close to £30 million in 2014, has fallen behind Ashley Young while United have been looking at other left-backs ahead of the summer transfer window.
Sources have told ESPN FC that Mourinho is interested in Tottenham Hotspur's Danny Rose, Juventus' Alex Sandro and Celtic's Kieran Tierney.
Marcel Bout, head of global scouting, has attended Celtic games specifically to watch Tierney.
Shaw has been left frustrated by a lack of opportunities this season that has effectively cost him the chance of going to the World Cup with England.
Sources have told ESPN FC that Shaw believed he had a chance of being selected for friendlies against Netherlands and Italy last month after a run of eight starts in 11 games for United through January and February, but he was omitted by manager Gareth Southgate -- a fan of Shaw -- in favour of Rose, Young and Ryan Bertrand.
Shaw has not played a single minute of first-team football since the international break and has been left relying on injuries to other squad members to secure a seat on the plane to Russia.