Francis Coquelin
Francis Coquelin has been key for Arsene Wenger since returning from his Charlton Athletic loan in DecemberReuters

Arsenal manager Arsene Wenger says Francis Coquelin was not "happy" when he recalled him from his loan spell at Charlton Athletic in December 2014 because he thought he was going just a back-up but the France midfielder has eventually become a crucial asset in the Gunners line-up.

Having failed to establish himself at the Emirates Stadium since his move from Stade Lavallois in 2008, Wenger sent Coquelin on loan in November 2014 after he spent the previous campaign at Freiburg.

But Wenger was forced to recall him a month later due to a number of injuries in Arsenal's midfield.

Coquelin, 23, was then expected to be back-up for Mathieu Flamini but has become a crucial player for Wenger during Arsenal's impressive second part of the campaign, while earning a new contract at the Emirates Stadium.

"I explained to him that what I liked most was his ball-winning potential rather than his playmaking potential, so I sent him out on loan to France for experience," Wenger explained.

"He played without being convincing in the box-to-box role. He then went to Charlton and I sent somebody to watch him. The reports were positive and I called him back after five weeks, and he wasn't happy. I said to him, 'why are you not happy?' and he said, 'I was playing regularly for Charlton and you called me back just to cover and not to play me'.

"We went into the first game and I didn't start him. Then we went to West Ham United and I started him. He was surprised because we played at home against QPR and I didn't play him, but I did away at West Ham."

Coquelin has started 16 Premier League games since his return from Charlton and played a crucial role in the team's run to the FA Cup final.

"Since then, he has not moved out of the team because he sticks to what he is strong at: winning the ball and using it well. What is also surprising is that he's very good in the air because he has a very good leap," Wenger added.

"I always remind him that we have gone through a long period of suffering and I tell him not to forget that – always remember who you are. That is a very great example for young kids because you make a career with one dominant quality, but sometimes you forget who you are."

Wenger points out Coquelin signed as a prospect for the future in 2008 and has needed almost seven years to established himself in the first team. The manager has urged other young players to follow in Coquelin's footsteps in the future with the same patience.

The French boss said: "He's a good example but the other good example is that he arrived at 17 and has finally made it at 24. It's unbelievable how patient and open-minded you have to be."