The Philadelphia Eagles may have signed their best rookies after the draft ended Saturday night.

They have high hopes for the seven players they picked during the draft, especially early-round selections outside linebacker Marcus Smith, wide receivers Jordan Matthews and Josh Huff, and defensive back Jaylen Watkins. But don’t be surprised if a few of the 15 undrafted rookie free agents they added Saturday are on the 53-man roster when the Eagles open the regular season against Jacksonville on Sept. 7.

The Eagles seem to unearth talented players who are somehow bypassed in the draft every year. Last season, linebacker Jake Knott, nose tackle Damion Square and tackle Matt Tobin all made the roster as rookie free agents while running back Matthew Tucker earned a spot on the practice squad. In 2012, tight end/fullback Emil Ingwenagu, wide receiver Damaris Johnson and running back Chris Polk made it. Defensive end Cedric Thornton was an undrafted player in 2011.

At least four other players on the Eagles’ current roster — defensive end Brandon Bair, long snapper Jon Dorenbos, wide receiver Jeff Maehl and tackle Jason Peters — entered the NFL as rookie free agents with other teams.

Peters, a six-time Pro Bowler, spent his rookie season with Buffalo in 2004 as a backup tight end out of the University of Arkansas.

“This whole process is such an inexact science,” Eagles coach Chip Kelly said. “How in the world did Jason Peters not get drafted?”

Because the Eagles did not draft an offensive lineman this year, free agents Josh Andrews (Oregon State), Karim Barton (Morgan State), Kevin Graf (USC) and Donald Hawkins (Texas) will be competing with Tobin, Dennis Kelly, Julian Vandervelde and others for backup roles behind Peters, tackle Lane Johnson, guards Todd Herremans and Evan Mathis, and center Jason Kelce.

Andrews, a 6-foot-2, 311-pound guard, started 30 straight games for Oregon State. Graf, a 6-6, 309-pound tackle, was a three-year starter for USC.

The list also includes a former South Jersey high school standout in Rutgers wide receiver Quaron Pratt, a graduate of Palmyra High School. Pratt was named Rutgers’ Most Valuable Player after last season, which saw him catch 32 passes for 516 yards and also score on a 99-yard kickoff return.

Florida tight end Trey Burton is an intriguing prospect because of his versatility. The 6-2, 224-pounder played quarterback, fullback, tight end and wide receiver for the Gators. He finished his four-year career with 720 rushing yards and 16 touchdowns on 141 carries and also had 107 receptions for 976 yards and four TDs.

The Eagles also found some competition for place-kicker Alex Henery by signing Vanderbilt’s Carey Spear.

Spear, a college teammate of Matthews, made 15 of 19 field goals last season as a senior after making 20 of 24 kicks as a junior. He also produced 46 touchbacks in 66 kickoffs last season, which was one of Henery’s weaknesses in 2013.

Henery was the second-most accurate kicker in NFL history after his first two seasons, making 87.9 percent of his field goals in 2011-12, but was 23 for 28 last season to drop to 86 percent on his career.

Contact David Weinberg:

609-272-7186

A graduate of Penn State University, I worked at the Carroll County Times in Westminster, Maryland, before joining The Press in 2013.