LAKE FOREST, Ill. -- The Chicago Bears are committing to quarterback Mitchell Trubisky for at least one more season, but there will be changes on offense.

Bears general manager Ryan Pace announced Tuesday that Trubisky will enter 2020 as the team's unquestioned starting quarterback but stopped short of saying whether the organization plans to exercise his fifth-year option for 2021.

"Yes, we do [feel comfortable with Trubisky as the starter]," Pace said. "I think with Mitch, as we go through it, we need more time in the coming months to evaluate everything, but the first thing that comes to mind for me is just consistency. You see moments, you see games, but for him [the issue is] stringing together better consistency. So you have the peaks and valleys. We just need to flatten that out.

"... Mitch is our starter. We believe in Mitch, and we believe in the progress that he's gonna continue to make."

While Trubisky gets a vote of confidence, offensive coordinator Mark Helfrich, offensive line coach Harry Hiestand, tight ends coach Kevin Gilbride and assistant special teams coach Brock Olivo have been fired.

Helfrich was in his second season as an NFL offensive coordinator, after serving as head coach at Oregon. Head coach Matt Nagy has handled the play-calling in Chicago, howerver.

The Bears have until May to exercise Trubisky's option year, which is expected to exceed $20 million.

"We're not at that point right now with the season ending just two days ago, so we're not at that point right now, and when we will, we'll let you guys know," Pace said.

Pace added that the 25-year-old quarterback could undergo offseason surgery on his left shoulder. Trubisky played the majority of the year with a partially torn labrum in his non-throwing shoulder, according to ESPN's Adam Schefter.

The second overall pick of the 2017 draft, Trubisky finished 27th in total QBR (40.0), tied for 27th in touchdown passes (17) and 21st in passing yards (3,138) in 2019. He entered Week 17 -- with Chicago already eliminated from playoff contention -- ranked 32nd in yards per completion and average yards per pass attempt, according to ESPN Stats & Information.

Chicago's offense wrapped up the regular season 29th in points scored per game (17.5) and total yards per game (296.8), 25th in passing yards per game (205.7) and 27th in rushing yards per game (91.1).

Last year, Trubisky passed for 3,223 yards, 24 touchdowns and 12 interceptions as the Bears won the NFC North with a 12-4 record.

"We go through this, and I don't think it's one person's fault as we go through this whole thing, there's a lot of factors in play we can talk about," Pace said. "But I think with Mitch, you know, especially with a young quarterback, in a lot of cases it's never going to be a straight line, it's never going to be linear. There are going to be ups and downs. And you see moments this year, you see games, you see him responding to adverse situations within a game, those are signs of positive improvement. We just need to smooth out those inconsistencies.

"I think it's just growth as a young quarterback. I think there's things happening around him, it's not just him. And he knows he needs to get better in those areas. We knew his experience coming out of college, switching schemes after Year 1, all those things, there's just a growth process we're watching take place."

Bears coach Matt Nagy -- the playcaller on offense -- said he already has specific goals set for Trubisky in 2020.

"No. 1 is going to be -- we talked about decision-making, but I want him to be a master at understanding coverages," Nagy said. "So when these defensive coordinators, they have different ways of showing different coverages, and they're good at it. Our first year here, I thought Mitch did a really good job of understanding the importance of getting in and out of the huddle with the verbiage that we have. We've also learned, not just with him but with our players, how to use that. The next step, we talked about it last year, was level 202, right?"

Pace and Nagy's confidence in Trubisky notwithstanding, the Bears could explore signing a proven quarterback in the offseason.

Current backups Chase Daniel and Tyler Bray are both scheduled to be free agents. The Bears paid Daniel, who played under Nagy in Kansas City, $6 million in 2019, but the veteran was no threat to overtake Trubisky, even when the third-year quarterback bottomed out during the Bears' four-game losing streak. Daniel appeared in five games for the Bears over the past two seasons but almost exclusively when Trubisky was injured.

"As we look at that [quarterback] room, we know that room is important, and really two of three quarterbacks in the room are free agents with Chase and Tyler both being out of contract," Pace said. "So that's something we'll look at this offseason. We always try to increase competition everywhere, especially in the backup roles, so it's something we'll look at."