Manchester United striker Wayne Rooney will fly home from his club's pre-season tour after suffering a hamstring injury during training today.

Rooney's future has been the subject of persistent transfer speculation this summer, but the England international flew out to Thailand with his United teammates earlier this week.

United boss David Moyes had planned to use Rooney on a tour of the Far East that also includes matches in Australia and Japan.

The club's official Twitter account confirmed the news that Rooney will return home for a treatment on a hamstring problem, which is expected to rule the forward out for at least a month.

A tweet posted this evening by United read: "Wayne Rooney to fly home from #mutour after sustaining a hamstring injury.

"It is anticipated Rooney will be unavailable for selection for a month."

The 28-year-old is now a huge doubt for United's opening Premier League match of the season against Swansea City on August 17.