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When the Chicago Bears hired Vic Fangio as defensive coordinator earlier this offseason and decided to run a 3-4 defense, the team knew it needed to add some experience to the outside linebacker position.

Outside linebacker Pernell McPhee has received most of the attention this offseason after signing a five-year, $38.75 million contract with the team, but Chicago's other free-agent signing—veteran Sam Acho—has a chance to be a surprise starter at the other open outside linebacker spot in 2015.

As it currently stands, the Bears have seven outside linebackers on the roster competing for two starting spots.

Outside Linebackers on Chicago's Roster Name Height Weight Experience Sam Acho 6'3" 257 lbs 5 Jared Allen 6'6" 255 lbs 12 David Bass 6'4" 260 lbs 3 Lamarr Houston 6'3" 270 lbs 6 Pernell McPhee 6'3" 275 lbs 5 Kyle Woestmann 6'3" 260 lbs Rookie Willie Young 6'4" 251 lbs 6 Source: ChicagoBears.com

Among that group of outside linebackers, only McPhee and Acho have played the position at the NFL level. Rookie Kyle Woestmann spent last season at Vanderbilt as an outside linebacker after beginning his collegiate career as a 4-3 defensive end, and Jared Allen, Lamarr Houston, Willie Young and David Bass are all making that same transition this offseason.

While Allen, Houston and Young are all more recognizable names, Acho has a chance to slide into the starting lineup opposite of McPhee because of his experience.

A four-year contributor at the University of Texas, Acho registered 137 total tackles, 32.5 tackles for loss and 21 sacks in 49 career games for the Longhorns. The Arizona Cardinals selected him in the fourth round of the 2011 draft, and he converted from 4-3 defensive end to 3-4 outside linebacker in defensive coordinator Ray Horton's scheme.

According to Pro Football Focus, Acho played 575 snaps his rookie season, and he finished the year with 40 tackles, seven sacks, two pass deflections and four forced fumbles. He started all 16 games in 2012 at outside linebacker and finished the year with 48 tackles, four sacks, three pass deflections, two interceptions and two forced fumbles.

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He began the 2013 season as Arizona's starter on the left side, but he broke his leg against the New Orleans Saints in Week 3 and missed the remainder of the season. He returned from his broken leg last season but only made four starts. Acho appeared in all 16 games and finished the year with 31 tackles, one sack, three pass deflections and one interception.

The Cardinals opted not to re-sign him this offseason, and the Bears signed him to a one-year, $825,000 contract in April.

During OTAs in early June, Acho spoke about how comfortable he is in Chicago.

“I couldn’t be happier to be here,” he said, per Larry Mayer of ChicagoBears.com. “This couldn’t be a better fit for me, from a physical perspective and what we can do on the defensive side of the ball—and also just as a team, getting to know these guys in the locker room. It’s a great locker room and a great bunch of guys and I’m excited to be a part of it.”

The most important thing Acho brings to Chicago's defense is his experience playing in a 3-4 defense, but he knows he brings more than just that to the table.

"I've played it before. I know a lot about what teams are going to do," he said, per Kevin Fishbain of ChicagoFootball.com. "At the same time, every 3-4 is not the same, every coordinator is not the same. Leadership, experience, physical play and playmaking is what I bring and I think what a lot of guys are going to bring, too."

McPhee is the clear-cut favorite to be one of the team's starters on the outside, but the other job appears to be an open competition between Acho, Allen, Houston, Young and Bass. Acho has said all the right things off the field this offseason, and he has been impressive at times on the field in training camp.

Training camp has been in full swing for just over a week, and Acho has flashed during practice, according to BearReport.com's Jeremy Stoltz, the Daily Herald's Bob LeGere and ChicagoFootball.com's Nate Atkins:

The Bears held a practice/scrimmage on Saturday at Soldier Field, and Acho ran with the first-team defense with McPhee sidelined, according to LeGere:

In addition to making plays on the field, Acho also received praise from a teammate.

“He’s a beast, man,” said inside linebacker Christian Jones, according to Atkins. “He plays hard every down. He’s a physical guy. That’s what we like to have on the edge, guys who can take on those blocks and be able to make plays on the edge.”

McPhee will be expected to be Chicago's primary pass-rusher, meaning the other starting outside linebacker will have to be effective against the run.

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After struggling against the run in his first few years in the league, Acho developed into an effective run-stopper last season. According to Pro Football Focus, in 174 snaps against the run in 2014, Acho recorded 10 tackles, 10 assists and was credited with nine stops. He finished the season with a plus-5.0 grade against the run.

Acho does a nice job of setting the edge versus the run and knows how to break free from blockers, but he will have to prove in the coming weeks that he is more versatile and reliable than Allen, Young, Houston and Bass as an every-down linebacker.

Allen is one of the league's all-time best pass-rushers, but he is 33 years old and is playing out of a two-point stance for the first time in his career. He was effective against the run last season, but he will be asked primarily to rush the passer in 2015. If he does not secure one of the starting outside linebacker jobs, he will be used as a situational pass-rusher.

Both Young and Houston are coming off season-ending injuries and are playing 3-4 outside linebacker for the first time. Young was Chicago's best pass-rusher last season and recorded a career-high 10 sacks, but he lacks the athleticism to be an every-down outside linebacker.

Houston has experience playing out of a two-point stance from his days with the Oakland Raiders, and he—along with Bass—will be Acho's toughest competition on the outside. Bass is a fluid athlete who moves well in space, but he is still a bit raw and needs to work on his technique.

Houston has been effective against the run throughout his career and has flashed as a pass-rusher, but Acho's experience and ability against the run make him a surprise front-runner for the starting job.

“Whether you’re going with the 1's, 2's, 3's, everybody’s got a battle that they’re fighting,” Acho said, per Atkins. “… I heard a coach say, ‘It’s one thing to be a starter. It’s another thing to be a productive starter.’ So at the end of the day, I’m trying to just master my craft."

One of the starting outside linebacker jobs has not been handed to Acho this offseason, but if he continues to make plays in training camp and in the preseason, he appears to be a prime candidate to line up opposite of McPhee when the Bears take on the Green Bay Packers in Week 1 at Soldier Field next month.

Statistical information courtesy of NFL.com and Sports-Reference.com unless otherwise noted. Contract information courtesy of Spotrac.

Matt Eurich is a Chicago Bears featured columnist for Bleacher Report and a member of the Pro Football Writers of America.

Follow @MattEurich.