LeGere: Positions to watch in Bears' first preseason game

BOURBONNAIS - Players will begin the process of picking coach John Fox's 2015 Bears team Thursday night in the preseason opener against the Miami Dolphins at Soldier Field.

That's not a misprint, just Fox's philosophy.

"I explain to players that they pick the team basically with their performance," the Bears' coach said. "We need to start that Thursday night."

Because of the Bears' revamped coaching staff, last year's poor performance and a defensive scheme conversion from a base 4-3 to a 3-4, there is more uncertainty regarding the depth chart than in most seasons. A lot of decisions must be made before the final cutdown on Sept. 5.

If not against the Dolphins, then at some point in the preseason, an unheralded young player or obscure veteran will rise up and lay claim to one of the 53 roster spots. Fox experienced similarly unstable rosters when he took over teams coming off abysmal seasons with the Carolina Panthers in 2002 and the Denver Broncos in 2011. The Panthers were 1-15 before Fox came aboard and the Broncos were 4-12 the year before Fox's hiring.

"A lot of times we've had guys that were college free agents that showed in games," Fox said. "Maybe not the first preseason game but through the four preseason games they caught the coaches' eyes and unseated maybe a veteran guy."

On a Bears team coming off a 5-11 disaster, there is uncertainty at almost every position - if not on the first team, then among the top backups. Certain positions, especially on defense, should be especially interesting to watch against Miami and throughout the preseason:

Safety

Three-time Pro Bowler Antrel Rolle is one half of the equation, and second-year man Brock Vereen has gotten most of the first-team reps alongside the veteran. But Ryan Mundy is a force to be reckoned with. Mundy started all 16 games for the Bears last year, he led the team with 85 solo tackles, tied for the lead with 4 interceptions and was second on the Bears with 108 total tackles. Mundy started nine games with Rolle in 2013 with the New York Giants.

Running back

Starter Matt Forte takes enough hits in the regular season, so his preseason workload is limited. That leaves plenty of opportunities for veteran Jacquizz Rodgers and the Bears' two previous fourth-round picks, Jeremy Langford (2015) and Ka'Deem Carey (2014). Even further down the depth chart there is competition from Senorise Perry and Daniel Thomas, Nos. 5 and 6, respectively. Perry made the roster as an undrafted rookie last season and led the team in special teams tackles. The veteran Thomas, at 6-foot-1 and 230 pounds, is the biggest back on the roster and a possible short-yardage option.

Inside linebacker

Shea McClellin and Christian Jones have been running with the ones all camp, but they could be pressed by Mason Foster and Jon Bostic.

"He's built a good foundation in the spring, during the OTAs and the mini-camps, and he's getting more comfortable," linebackers coach Glenn Pires said of McClellin, who's moving from outside linebacker to inside. "He's far away from where we want him to be because now it's the physical part. He's going in the right direction, but I'm really anxious to see these preseason games."

Foster started 54 games in his first four NFL seasons, all with the Tampa Bay Buccaneers. Bostic was the team's leading tackler last season and has started 17 games since the Bears drafted him in the second round in 2013. Bostic got off to a slow start in camp after missing most of the off-season with a back injury.

Outside linebacker

Pernell McPhee is projected as one of the keys to the new defense and will anchor one side. But it's a toss-up as to who he will be paired with.

Jared Allen is listed on the unofficial depth chart as the other starter, but he's still transitioning from playing his entire football life as a defensive end. Sam Acho is the top contender for the other starting position. He played his previous four seasons in the Arizona Cardinals' 3-4 scheme and started 32 games. After getting 7 sacks as a rookie in 2011, Acho has just 6 in the previous three seasons and only 2 in the last two years.

Cornerback

Kyle Fuller is entrenched, and Tim Jennings probably fits best as the nickel, but he's listed, for now, as the other starter outside. Veteran special teams standout Sherrick McManis has gotten a lot of snaps with the first team in camp. McManis has the size - 6-foot-1 and 197 pounds - necessary to match up with big wide receivers, as does 6-foot-2, 195-pound, eight-year veteran Alan Ball. Another eight-year veteran, 5-foot-11, 190-pound Tracy Porter, is among the top contenders.

Al Louis-Jean (6-1, 193) left Boston College as a 20-year-old with a year of eligibility remaining but went undrafted. The Bears signed him, and he saw action in nine games and continues to mature.

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