Eric Prisbell

USA TODAY Sports

Once coach John Fox wrapped up his first season in Chicago, a 6-10 campaign beset by injuries, the Bears made a concerted effort to bolster their defense. They addressed it in the draft and free agency, upgrading a unit that had made strides in 2015.

But guess again if you think the unit will be the determining factor in the Bears' success in 2016.

As is usually the case in recent seasons, Chicago's playoff hopes figure to boil down to the player who has long been the Bears' most polarizing figure: Yes, it's all about Jay Cutler.

All he did in 2015 was author the best statistical season of his uneven professional career. He was unquestionably the team's most valuable player, registering a personal-best passer rating (92.3) and drastically cutting his interception total (18 to 11) despite a depleted wide receiver corps.

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Now Cutler has to do it again. And he will need to repeat his performance with a number of factors working for and against him.

Cutler, 33, is working under his sixth offensive coordinator since 2009. He had a great relationship with Adam Gase, who departed to become head coach of the Miami Dolphins. He started cultivating a relationship last year with Dowell Loggains, the 35-year-old who was promoted from quarterbacks coach to offensive coordinator.

"We definitely could be better," Loggains says. "I think it's a mutual respect. Whatever I say to him, he knows where it's coming from and vice versa."

As for personnel, Cutler won't be able to rely on departed running back Matt Forte, who was a stalwart for the Bears since 2008. It remains to be seen whether Jeremy Langford or a committee of backs can fill that void.

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Provided they remain healthy, Cutler's receivers could be special. Alshon Jeffery and Kevin White will finally be on the field together after injury-plagued seasons in 2015.

Jeffery was limited to nine games because of a variety of ailments: calf, shoulder, groin and hamstring. White, a first-round pick from West Virginia in 2015, missed the season because he had a stress fracture in a shin.

The Bears can ill afford a repeat of their 1-7 record at home or 1-5 record in the NFC North if they hope to secure a playoff berth. But they have a more manageable schedule and should at least be in the playoff hunt in Fox's second season … if Cutler can avoid regressing.

Quarterback

The best version of Cutler, who has long been a lightning rod for criticism, is capable of leading a formidable offense. But he has not played in all 16 games since 2009. Important was the under-the-radar signing of backup Brian Hoyer, 30, who has appeared in 43 games with 26 starts since 2009. "He gives you an established backup, a veteran guy," Loggains says. "There's competition. He gives us a guy who has played in the league and has a winning record as a starter."

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Running back

Forte's contributions since 2008 were significant, and he is second in career rushing yards (8,602) for the Bears. But Chicago made no effort to re-sign him. Langford is the favorite to be the No. 1 back. He started two games last season, joining Gale Sayers and Walter Payton as the only Bears rookies since 1960 to run for touchdowns in four consecutive games. Jordan Howard, Ka'Deem Carey and Jacquizz Rodgers also are in the mix. As Fox said, "It's hard to get through a season with one back, from a health standpoint, when you have 11 guys chasing a guy around."

Wide receiver

Jeffery, a second-round pick in 2012, had three consecutive 100-yard games despite his limited availability. He signed his franchise tag tender, which guarantees him $14.6 million, but could still receiver a long-term deal. Eddie Royal, who missed seven games himself last season, should be in the slot. There's plenty of excitement about White, who had 109 catches for 1,447 yards and 10 touchdowns at West Virginia in 2014. "He is everything that we expected," Loggains says of White. "His attitude is contagious because he is very positive. He doesn't have bad days."

Tight end

When the Bears traded Martellus Bennett to the New England Patriots, it was clear that they thought they could lean on Zach Miller, provided he can stay on the field. He had 34 receptions for 439 yards with five touchdowns last season, the first he'd played since 2011. All of his touchdowns came in the final eight games in which he played.

Offensive line

It could be a work in progress. Right guard Kyle Long, a three-time Pro Bowler, and right tackle Bobby Massie are in place. Left tackle Charles Leno is also set to start. Second-round pick Cody Whitehair can play guard or center and should compete at left guard with Ted Larsen. Center Hroniss Grasu is in his second season.

Defensive line

Chicago clearly needs better play here as it continues to adapt to a three-man front. It took a step in the right direction by bringing in Akiem Hicks via free agency. Drafting Jonathan Bullard in the third round could be a shrewd move. Defensive end Ego Ferguson battled injuries late last season but should be a factor. Eddie Goldman had an impressive rookie season (22 tackles, 4½ sacks).

Linebacker

The Bears seemed to make significant strides by acquiring Danny Trevathan and Jerrell Freeman to man the middle. Trevathan, who played for Fox with the Denver Broncos, should be a cornerstone for the defense after leading Denver in combined tackles in 2015. Willie Young moved from defensive end to outside linebacker as the Bears moved to a 3-4 scheme. He led the team in tackles for losses. Keep an eye on ninth overall pick Leonard Floyd. At 6-6, 244 pounds, he can stand to gain weight and strength. He has speed and athleticism but only collected 4½ sacks last season at Georgia. Pernell McPhee is stout against the run and can get to quarterbacks, too. Lamarr Houston is coming off a major knee injury.

Secondary

It will continue to come under heavy scrutiny after another underwhelming performance last season. It might be the team's worst position group. Chicago intercepted eight passes last season, tied for second worst in the league. At cornerback, Kyle Fuller was a first-round selection two years ago, but it remains to be seen if he is a viable long-term starter. Tracy Porter, who has played for five teams since 2011, is back in the fold. The Bears picked two safeties in the fourth round, hard-hitting Deon Bush and Deiondre Hall.

Special teams

Kicker Robbie Gould is the team's all-time scoring leader, but 2015 was a down season for him. He made 33of 39 field-goal attempts, missing a couple in the waning moments of tight games.

Coaching

Fox, 61, has a track record of turning around franchises and making them title contenders. He has taken two teams, the Carolina Panthers and Broncos, to the Super Bowl. Coordinator Vic Fangio helped the defense improve last season, and the unit is positioned to take another step forward. Loggains draws a tough assignment in replacing Gase.

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Follow Eric Prisbell on Twitter @EricPrisbell

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