Luke Shaw Injured, Replaced by Antonio Valencia vs. Swansea City

Manchester United defender Luke Shaw hobbled out of the team's Premier League clash with Swansea City on Sunday. 

The club's official Twitter account confirmed the problem, with Antonio Valencia coming on to replace the England international after only nine minutes:

The left-back has suffered a series of injuries since arriving at Old Trafford from Southampton in 2014, and he was ruled out for a number of weeks at the start of the campaign with a groin tear, according to BBC Sport.

Shaw suffered a leg fracture early last season, and he spent the rest of the 2015/16 campaign on the sidelines.

The 21-year-old is considered one of the most promising youngsters in Europe, but he has found it difficult to affect coach Jose Mourinho's plans.

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Ex-United boss Louis van Gaal watched on as his team regressed without Shaw in his defence, but Mourinho has put his faith in Daley Blind, Marcos Rojo, Matteo Darmian and even Ashley Young ahead of the left-back since he recovered from the aforementioned groin problem.

The Red Devils head coach has criticised Shaw but has said there is no problem between himself and the defender, according to Jack Austin of The Independent.

Another injury at this time in Shaw's career could have a negative impact in light of his recent bad luck in that regard.

United will miss Shaw, and Mourinho will have to run the rule on his auxiliary options while the left-back recovers.

The England international has much potential, but he must prove his drive and long-term fitness before he attains a regular starting position.