The 2014 season was a very, very good one for the Buffalo Bills defense and coordinator Jim Schwartz. The Bills had it all going on, allowing the second-fewest points in the league, topping the NFL in third-down defense and posting the second-lowest cumulative quarterback rating of the 32 teams.

It all worked for Schwartz and his defense that season.

Among the many pieces on the field for the Bills that year was cornerback Leodis McKelvin, a former Buffalo first-round draft pick who recorded four interceptions in 10 games and who impressed Schwartz in a number of ways.

Now that McKelvin is an Eagle after signing a two-year contract on Tuesday, Schwartz talked about the all-around cornerback who was all over the football just two seasons ago.

"He's had a long history as a player, was drafted in the first round (11th overall, 2008) and, other than some injuries, has always played at a really high level," Schwartz said in his NovaCare Complex office. "He can play inside, he can play outside, he was a good tackler, had great ball instincts, was a good, all-around player and has been that way for a long time."

McKelvin saw action in 98 games for Buffalo and started 60 games, picking off 12 passes, making 305 tackles and playing bigger than his listing -- 5 feet 10, 185 pounds -- for the Bills. McKelvin has battled injuries (a fractured ankle, suffered late in the 2014 campaign) the last couple of seasons -- he played in those 10 games in 2014 in Schwartz' single season in Buffalo and was limited to nine games and five starts (one at safety, four at cornerback) for the Bills in 2015.

He's here to compete for playing time at cornerback for the Eagles, but Schwartz is one of those coaches who doesn't like to put his players in a box. Maybe McKelvin challenges for a starting job outside. Maybe he becomes a slot cornerback here in the nickel. Safety? At 185 pounds it would seem to be a stretch, but we don't know a whole lot about how Schwartz sees his personnel.

He just sees McKelvin as an asset who has worked hard to improve at things like being around the football and making plays on the ball.

"That's something he's really worked on," Schwartz said. "Early in his career he had trouble locating the ball down the field. That was one of the holes in his game. But like a true pro over time, he got better at that and worked at that and it became a strength. The year I was with him in Buffalo he had a couple of outstanding interceptions where, even though he's only a little bit above 5-10, he out-jumped guys who were much taller than him, went up and played the ball in the air. He was on his way to an outstanding year in Buffalo that year before he got hurt.

"The biggest thing for defensive backs is the ability to cover man to man and he can do that. You can add other things in there. You can add zone and things like that, but it all comes down to locking a player down. It's not just a skill set. There's a mentality that comes along with that. You can't be afraid of the spotlight that's on the outside part of the field. It's a difficult assignment. You're not going to win every time, but you can't lose confidence if you allow a completion, and Leodis doesn't. He battles, he competes and I think that shows in his play."

Schwartz said that McKelvin is "aggressive and he does throw his body around" when it comes to tackling -- "He probably tackles bigger than his size" -- and it's another attractive attribute for McKelvin and a secondary that is having a transformation in personnel, in mentality and in the scheme that Schwartz brings to Philadelphia.

How McKelvin fits it is yet to be determined. Schwartz wants to get his players on the field before he makes his decisions on who plays where. What the Eagles did on Tuesday was bring in a veteran who had a great deal of success in his one year playing with Schwartz, who understands the system and who is going to add competition to an area of need.

And if McKelvin plays at the level he did under Schwartz in 2014, the cornerback position will be upgraded.