With help from an NFL preseason that has not yet shrunk from four to two games, undrafted rookies and under-appreciated veterans took advantage with surprising performances that earned a first, or one more, chance on a team roster.

In the AFC, the undrafted free-agent rookies included cornerback Malcolm Butler from little West Alabama and inside linebacker Zach Orr out of North Texas. This week Butler will often line up at New England Patriots practice on the same unit with the great Darrelle Revis. Orr is with the Baltimore Ravens as a special teams standout who also works out at the same position recently held by legendary linebacker Ray Lewis.

And in Pittsburgh, wide receiver Darrius Heyward-Bey, the former first-round pick (Oakland, 2009, No. 7 overall) known for being all speed and no hands, surprised coaches and teammates by converting his slim chance into a sixth season in the league.

Here is a closer look as the Surprises of Summer from all AFC training camps, as reported by correspondents covering each team for The Sports Xchange (teams listed in alphabetical order within each division):

AFC EAST

BUFFALO BILLS

--SURPRISE OF SUMMER: Offensive tackle Seantrel Henderson.

A rookie, seventh-round draft pick, Henderson went from a player almost not drafted in May due to his checkered off-field past at the University of Miami, to someone who will likely start at right tackle Sunday when the Bills travel to Chicago to take on the Bears.

In training camp, Henderson filled in at left tackle for Cordy Glenn who missed three weeks with a medical condition, and more than held his own. When Glenn returned, Henderson was switched to the right side where he played in college, and though he made some rookie mistakes, Henderson held up well and is the Bills' best option at the position.

MIAMI DOLPHINS

--SURPRISE OF SUMMER: Defensive end Terrence Fede.

The seventh-round pick from Marist missed the preseason finale with a knee injury, but already proved he is a raw talent with unrefined technique but he gets upfield effectively in passing situations and gives a good effort against the run.

He is expected to be in the rotation at defensive end.

NEW ENGLAND PATRIOTS

--SURPRISE OF SUMMER: Cornerback Malcolm Butler.

Like so many undrafted free agents, Butler was perceived as an afterthought signing last May. The 5-foot-11, 190-pound corner out of FCS (Div. II) West Alabama was just a name on the roster heading into training camp.

But then he took reps with the first defense and took significant time at both corner spots opposite Darrelle Revis and Brandon Browner. He spent the summer proving himself a physical, feisty corner.

Given Browner's season-opening four-game suspension, Butler will have more chances to continue his rise from unknown to rotational option in the Patriots' retooled secondary.

NEW YORK JETS

--SURPRISE OF SUMMER: Wide receiver Saalim Hakim.

Hakim wasn't even on the radar when training camp began, but the former practice squad player surged past veterans Jacoby Ford and Clyde Gates to win the primary kick returner job. His deep speed should also allow him to factor into the offense as a situational threat.

AFC NORTH

BALTIMORE RAVENS

--SURPRISE OF SUMMER: Inside linebacker Zach Orr.

This undrafted rookie out of North Texas beat the odds to make the Ravens' roster. Orr primarily made the cut through his special-teams prowess. He had a big hit on special teams in the preseason finale. Orr wasn't expected to make the team at the start of training camp.