Ronald Koeman has backed Maya Yoshida to solve his left back crisis as Saints aim to keep their European challenge on track with victory over West Ham tomorrow night.

The Japanese international was drafted into the makeshift full back position just 20 minutes into the 1-0 win over QPR due to Matt Targett’s head injury.

Targett was in the side in place of Ryan Bertrand, who is serving a three match suspension.

With Targett needing a week to recover from his concussion and Bertrand out for a further two games, Koeman has a dilemma ahead of the visit of the Hammers.

He could play three centre halves, or stick with a flat back four, which is likely to be his preferred option given the problems that Eljero Elia and Sadio Mane caused at the top of that formation against Rangers.

If that is the case then Yoshida is likely to have to continue at left back, with the only other option being to switch Nathaniel Clyne and play Yoshida at right back.

However, after his excellent performance against QPR, Koeman has no fears over Yoshida at left back.

“I was very happy about all the defenders. Happy about Maya,” he said. “You are always lucky as a manager when you have players like him because he can play on different positions.

“I was asking him because the best is always to change one position. If I put Clyne to the left and Maya to the right I have to change more than one position.

“I said to Maya ‘are you comfortable on the left side’ and he said ‘it doesn’t matter.’

“That’s fantastic because that’s team work but Florin (Gardos) did a great job, Jose (Fonte) did a great job and Clyney and the goalkeeper.

“I think it was the 11th or 12th clean sheet this season and this is the key to the team being successful this season.”

Saints really felt the benefit of a much stronger squad for the game at QPR with Yoshida and match winning goalscorer Mane both back from international duty.

“Maybe the nation of Japan was not so happy that they lost on penalties but I was happy because I got a player back and we don’t have so many players back to say keep going in the Asia Cup,” smiled Koeman.

“It’s the same question about Sadio because little by little we will have the players available for the last 14 tough games we have and that a great feeling.”