The Chicago Bears and Buffalo Bills shared a joint practice on Friday ahead of their preseason matchup on Sunday. All eyes during training camp have been on quarterback Caleb Williams as he hopes to improve from an up-and-down rookie season.

During his rookie season last year, Williams played in all 17 regular season games. He completed 62.5 percent of his pass attempts for 3,541 yards, 20 touchdowns, and six interceptions. Also, the 23-year-old quarterback ran for 489 yards on 81 attempts.

We break down Friday's joint practice between the Bears and Bills — how the two starting quarterbacks fared and Mitch Trubisky's return.