After joining Everton just a year and a half ago Muhamed Besic was struggling for playing time as well as with injuries, but since James McCarthy went down injured he has taken hold of the right side defensive midfielder role and won a place in the fans' hearts. His aggressive defense and impressive passing has given the team a different element and helped improve the side.
Averaging nearly three tackles a game and yet completing 87% of passes shows how impressive he's been for Everton. It's unclear what Roberto Martinez will do when McCarthy returns, but Besic has surely worked his way into a more consistent role. That said McCarthy has also averaged nearly three tackles per game and 87% pass completed this season. I would argue though that McCarthy has a more reserved game and prefers back passes while Besic is more aggressive and is willing to try more attacking passes.
A new contract to solidify his future at Everton would be welcome by the fans right now and would have to go at least five years in length to make the team happy since he still has over three years on the current deal. The end result though is a happy player with a long term future at the club and someone the team can build around. Especially as Gareth Barry ages and only has one and a half years left on his deal