Southampton manager Ronald Koeman has expressed his joy after Ryan Bertrand sealed a permanent deal at St Mary's.

The Saints opted to take up a reported £10m permanent option on Bertrand's loan deal from Chelsea on transfer deadline day.

"That was very good news," Koeman told Southampton's official YouTube channel. "We've been working hard to have Ryan for more time in the club, and finally we agreed and the club did a good job because he's doing well, he's a good player.

"Left-back is a difficult position to have a good one in the team. Ryan can play a longer time for Saints, and that is good news for us."

Bertrand has made 27 appearances in all competitions so far this season.