This week, we examine several key Miami Dolphins players who have a lot to prove in 2014.

Next, we take a look at Dolphins starting outside linebacker Koa Misi, who signed a four-year, $17 million contract extension during last season.

2013 stats: 54 tackles, 2 sacks

What he has to prove: Misi has to prove that he's still a full-time starter worthy of his long-term extension. Many were baffled why former Dolphins general manager Jeff Ireland signed Misi to a four-year extension when it appeared Misi still had more to prove. He played well at times but wasn’t consistent. Misi certainly didn’t make enough big plays.

Walker’s 2014 outlook: I’ve never been big on Misi. Therefore, my expectations are not high for him this upcoming season. Misi has solid athleticism but has never put it together in four seasons. Misi isn’t a draft bust, because he did develop into a starter as a former second-round pick. But Misi is not the difference-maker the Dolphins expected. For comparison’s sake, the New England Patriots took Pro Bowl tight end Rob Gronkowski, who is a difference-maker, just a few picks after Misi in 2010. Misi is a borderline starter who might be replaced this season if the Dolphins find an upgrade via the draft.