As the 2011 seasons draws closer to its halfway point and many teams fall out of contention, more first-year players are receiving opportunities to play at the expense of older veterans. Injuries have also continued to be a theme of the 2011 season after the lockout shortened training camps, allowing many rookies opportunities they may not have seen if it weren’t for the work stoppage. Chris Tripodi returns again this week with a new group of rookie evaluations.

Christian Ponder (QB-Min)

Out with the old, in with the new. That was the case in Minnesota this past week, as a 1-5 start and a sputtering offense was enough for coach Leslie Frazier to make a change at quarterback. The struggling Donovan McNabb was replaced by Ponder, the team’s first-round pick out of Florida State, and the move paid immediate dividends.

The Vikings still lost their game against the Packers and while Ponder didn’t exactly fill up the stat sheet, going 13-for-32 for 219 yards, 2 touchdowns and 2 interceptions, he showed enough poise and ability to give Minnesota fans hope that their first-round pick in April was well-spent.

Ponder looked poised and in command of the offense from the start, completing a 72-yard pass to Michael Jenkins on the first play of the game. He showed off his mobility with 4 carries for 31 yards and threw well on the run to his right and his left on designed rollouts. While he doesn’t possess great arm strength or the ability to drive throws deep down the field, Ponder makes up for it with a strong sense of anticipation.

The former Seminole made some mistakes on Sunday, but that’s to be expected from a rookie making his first start against the reigning Super Bowl champs. He struggled with elbow and shoulder injuries in his final two years at Florida State but if he can stay healthy, Ponder has the intangibles to make up for average physical ability and help him develop into a legitimate starter at the NFL level.

DeMarco Murray (RB-Dal)

A third-round pick out of Oklahoma, Murray sure didn’t play like a third-rounder against the Rams on Sunday. Tashard Choice drew the start for Dallas in place of the injured Felix Jones, but quickly took a backseat to Murray once the rookie took his first carry 91 yards up the middle for a touchdown. By the end of the day, Murray had rushed for an NFL season-high 253 yards on 25 carries and set a new Cowboys’ rookie rushing record, breaking Emmitt Smith’s mark of 237 yards.

Murray flashed the dominant ability on Sunday that was on display at times during his career with the Sooners. His upright running style and penchant for injury were the major reasons he dropped into the early part of round three but his speed (4.4), quickness, smooth running style and ability to make defenders miss were apparent against St. Louis.

Murray also stayed patient throughout most of his runs, setting up the blockers in front of him before exploding through the holes. The Rams have a sorry excuse for a defense, which certainly helped inflate the rookie’s statistics, but he looked good and quickly relegated Choice to a bench role. He didn’t catch a pass but has excellent receiving skills which are sure to be on display for the rest of the time Jones is sidelined and possibly beyond. Many experts thought Murray was nothing more than a potential third-down back in the NFL, likely due to the questions surrounding his durability. But he showed on Sunday that if he can stay on the field, Murray has game-breaking potential as a featured runner.

Phillip Tanner (RB-Dal)

DeMarco Murray wasn’t the only Cowboys rookie running back to receive extra work in lieu of Felix Jones’ injury, as the undrafted product out of Middle Tennessee State picked up a few carries in garbage time of Dallas’ blowout of the Rams.

With Choice hurting his shoulder during the game, Tanner finished as the primary backup for Murray and while the Oklahoma rookie didn’t need much help, Tanner was able to run for 34 yards and a touchdown on his first 6 career carries.

At 5-10, 210 pounds Tanner is a powerful runner who breaks arm tackles and finishes runs. He lacks the breakaway speed that Murray possesses, but can be effective catching the football out of the backfield as well. He’s not the threat to Choice and Felix Jones that Murray is but if those two can’t get healthy soon, Murray and Tanner look capable of handling the backfield in Big D.

Adrian Clayborn (DE-TB)

The first-rounder out of Iowa has started all seven games for Tampa Bay this season and has impressed lately after a quiet start to the season. Clayborn didn’t record a tackle in the first two weeks of the year, but has 11 tackles and 3 sacks in the five games since.

Despite shedding 20 pounds to get down to 265 since getting drafted by the Bucs, Clayborn has remained strong enough to set the right edge against the run, adding to his great first-step quickness off the snap. In addition, the shoulder issues that plagued him in college have not yet been an issue in the NFL.

Tampa Bay has struggled rushing the passer as a team with just 12 sacks, but Clayborn is not to blame for those issues. His explosiveness off the edge and ability to make plays in the backfield and in pursuit have made plenty of people forget about a disappointing senior season with the Hawkeyes. If second-round pick Da’Quan Bowers can remain healthy and develop on the other side, Tampa Bay won’t have issues rushing the passer for much longer.

Muhammad Wilkerson (DE-NYJ)

After a slow start to the season that included just three tackles in the first three games, the raw Temple product has stepped up for the Jets in recent weeks, recording 13 tackles (10 solo) and 2.5 tackles for loss in his last four games. His improved performance has been a big reason the Jets have seen slight improvement in their run defense in recent weeks.

After being drafted 30th overall in the first round back in April, Wilkerson is learning on the fly in the starting lineup. He sacked Luke McCown for a safety in Week 2 and has been slowly gaining confidence as he gets more comfortable at defensive end in the 3-4 defense after playing three-technique tackle with the Owls.

Wilkerson lacks the bulk to be a nose tackle in the NFL at just 6-4, 315 pounds. He’s been effective as a two-gap end and is the Jets’ most talented defensive lineman, even if the polish isn’t quite there yet. Wilkerson has the frame to add weight without losing speed and is extremely athletic and fluid moving along the line. If he continues to grow as a player and develop more moves with his hands to shed blocks, Wilkerson has the upside to enjoy a long, successful career at multiple positions along the defensive line.

K.J. Wright (LB-Sea)

A fourth-round pick out of Mississippi State, Wright outplayed former 2009 top-five pick Aaron Curry and took over the starting strong-side linebacker role just two weeks into the season. The Seahawks were impressed enough with Wright’s performance in the following weeks that they essentially gave Curry away to the Raiders for a 2012 seventh-round pick and conditional late-round pick in 2013.

In four games since being promoted to the starting role, Wright has 13 tackles (9 solo). He had his best game to date on Sunday at Cleveland with 7 tackles (6 solo) and one for loss as the Browns ran for 141 yards on the day, but took 44 carries to reach that number.

Wright is a great athlete with an excellent combination of size (6-3, 246) and speed (4.75). He has the ability to be a playmaker both in pursuit and in coverage, showing a quick first step and getting depth on his pass drops. The major knock on Curry in his first two seasons was a lack of football instincts and while Wright is still a work in progress in terms of awareness, he has made impressive strides as a rookie and continued improvement should be expected.

Sam Acho (LB-Ari)

After seeing action on just 36 snaps in Arizona’s first six games of the season, the former Longhorn saw his most action to date in Sunday’s loss to the Steelers. Acho recorded his first 2 tackles of the season, along with his first career sack of Ben Roethlisberger.

Defensive coordinator Ray Horton has called Acho a “brilliant football player” and with the Cardinals falling out of contention after five straight losses and O’Brien Schofield struggling to pick up the playbook, Acho will continue to see more reps at the expense of veteran outside linebacker Joey Porter.

A defensive end at Texas who the Cardinals drafted in the fourth round back in April, Acho is a smart player with a good first step and an ability to penetrate the gap. He has the speed (4.62) to flow sideline-to-sideline and get into the backfield to make plays behind the line of scrimmage. Acho struggled at the point of attack in college, but lining up on the outside of Arizona’s 3-4 should play to his strengths.

Chris Conte (S-Chi)

To say the Bears have had issues at safety this season would be an understatement. Chris Harris and Brandon Meriweather started the season in the lineup but were both pulled after a Week 5 loss to Detroit in favor Conte, a third-round pick out of California, and Major Wright, who started in Week 6 but was inactive on Sunday due to a hip injury. Harris returned to the lineup in Wright’s stead and gave Chicago their sixth different set of starting safeties in seven games this season. Out of all the players the Bears have used at safety this season, Conte has the most upside.

Chicago has won two straight games in Conte’s first two career starts and he’s had an impact in both. He had 6 tackles (3 solo) against Minnesota in Week 6 and while he had just one tackle Sunday against the Bucs, he also broke up two passes and made his first career interception. Conte came up big with a 7-0 lead in the first quarter, nailing Tampa Bay’s Mike Williams just short of the goalline after a catch to knock the ball loose and grab the loose ball for the interception. In just one play, his aggression in going for the big hit was on display as well as his awareness to take the ball away from Williams.

The former Golden Bear has the speed (4.49) to be an effective center fielder and the potential to become a very complete NFL safety. He’s only had two starts so far, but Conte should continue to play free safety in Chicago in the foreseeable future.

Chris Tripodi has been writing for Draft Insider since 2009, compiling Rookie Reports and Draft Reviews and interviewing NFL prospects. He has been a sportswriter for multiple newspapers and has previously worked at ESPN and with the Rochester Red Wings, the Minnesota Twins’ Triple-A affiliate. Follow him on Twitter (@christripodi) and check out his blog at http://christripodisports.blogspot.com.