Pace also noted that the team will cut linebacker Willie Young later on Wednesday.
Glennon was signed to a three-year deal worth $45 million shortly after the Bears released Jay Cutler. Chicago then elected to trade up one spot in the 2017 NFL Draft and select quarterback Mitchell Tribusky.
The impending move comes as little surprise given the $2.5 million roster bonus and $12.5 million salary that Glennon is set to make under the terms of the deal he signed last year.
Trubisky completed 196 of 330 pass attempts for 2,193 yards, the most among rookie quarterbacks in franchise history. The 23-year-old also threw for seven touchdowns and seven interceptions in 12 games.
Glennon struggled in four starts with the Bears in 2017, throwing five interceptions and committing eight overall turnovers during the team's 1-3 stretch.
The 28-year-old Glennon has thrown for 4,933 yards with 34 touchdowns and 20 interceptions in 25 career games since being selected by the Tampa Bay Buccaneers in the third round of the 2013 NFL Draft.
Young played just four games last season before landing on injured reserve with a torn triceps. The team will clear $4.5 million off the cap when it releases the 32-year-old Young, who recorded 23.5 sacks in his previous three seasons with the Bears.