The Philadelphia Eagles signed Tim Tebow to a one-year contract in April, and Eagles fans, along with NFL critics, weren't sure that move was in the best interest of the team.

Tebow, 27, sat out the NFL's 2014 season and has not played in a regular-season game since 2012 as primarily a wildcat quarterback with the New York Jets, reports Sports Illustrated. The New England Patriots signed the University of Florida alum back in 2013 but later cut him during training camp.

The problem was with Tebow's throwing mechanics, which Eagles head coach Chip Kelly says have improved.

"I have seen an improvement from Tim since the day we got him in terms of his knowledge of what we're doing, understanding where everybody is," Kelly told the Delaware County Times on Wednesday.

"There's a whole process, and for him what we have done is different than what he's done anywhere else. So in terms of learning our terminology and how we do things, I think each week you've seen an incremental bump in him, so we're excited to see where that takes him and it'll be a good competition as we get into August," he continued.

While Tebow's critics point out that his throwing mechanics still require constant tweaking, they miss sight of his mobile dimension. It was mobile dimension that enabled him to seize a 2011 playoff victory for the Denver Broncos over the Pittsburgh Steelers with a touchdown pass in overtime, according to Sports Illustrated. The Heisman Trophy winner completed 10 of 21 passes in that game.

The Eagles currently have five quarterbacks under contract, according to Sports Illustrated. Sam Bradford will be the starter to open the season if his left knee has completely healed. Tebow will be competing with Matt Barkley for the third-string quarterback job.

Tebow played college football for the University of Florida, which led to his winning the Heisman Trophy in 2007. He also played on BCS National Championship-winning teams in the 2006 and 2008 seasons. Prior to the Eagles, Tebow played for the Denver Bronco, the New York Jets and briefly with the New England Patriots.