Southampton manager Ronald Koeman has revealed that summer signing Jordy Clasie could miss the Saints' start to the Premier League season with a hamstring injury.

Clasie - an £8m signing from Feyenoord - fell injured in Thursday's 3-0 Europa League qualifying win over Vitesse at St Mary's.

"Clasie had some hamstring problems - we will find out more tomorrow," the Dutchman is quoted as saying by The Mirror.

"It is possible he will miss the start of the season because hamstring injuries are always dangerous."

Graziano Pelle, Dusan Tadic and Shane Long did the damage as Koeman's side recorded their first European victory in 34 years.

The win puts Southampton in a commanding position to reach the playoffs - one qualifying round shy of the group stages.

The Saints kick off their league campaign with a trip to Newcastle United in nine days' time.