Southampton full-back Ryan Bertrand has been ruled out for between five and six weeks, leaving him in a race against time to be fit for the start of the new season.

The England international underwent minor knee surgery at the end of last month and now faces a spell on the sidelines.

Speaking on his side's return to pre-season training, Saints boss Ronald Koeman confirmed the news, while also revealing that a fresh face could now be brought in.

"Ryan Bertrand had a small surgery 10 days ago in both knees and he will be out for the next coming weeks," FourFourTwo quotes the Dutchman as saying.

"[He'll be out] around five, six weeks. The numbers of defenders we have is too small and we need more competition."

Asked about rumoured interest in FC Twente's Cuco Martina, he added: "That's true, we have an interest in the player and would like to sign the player. It's close."

Southampton begin their Premier League campaign with a trip to face Newcastle United on August 9.