John Mensah is determined to prove to Sunderland manager Steve Bruce that he can stay on his feet as he battles to rectify his image as a crock.Mensah, who is nicknamed the rock of Gilbratar, has struggled with injuries throughout his time at the club and could lose out on a permanent deal as a result. But Gyan says he can prove to the manager he can be reliable and insist that is a fact Sunderland is aware of already. "Sunderland know I have helped my nation and my previous clubs before, and they want me to play a lot for them. They know the kind of player I am," said Mensah. "I myself don't feel happy at all when I'm injured because if someone likes you, you should show why. If you don't play, it's difficult for people to know why the manager wants you." Mensah admits he has not been at his best this season but remains supremely confident in his own abilities. "I'm always confident but sometimes when I come back from injury it can be really difficult," said Mensah."But if you continue to keep playing you can see the confidence come back. I have a lot of confidence wherever I go. We all know Sunderland have a good team and the good teams have a good bench as well. Everyone on the bench, everyone who plays, is a good player at Sunderland, so we have to make sure we are determined to win the matches." Mensah is available for selection on Saturday when they travel to Goodison Park to face Everton.Source: Kickoff.com