(LAKE FOREST, IL) – Chicago Bears rookie quarterback Justin Fields will make his first career start Sunday as Andy Dalton is expected to be out with a left knee injury, coach Matt Nagy told reporters Wednesday. Nick Foles will serve as Fields' backup Sunday against the Cleveland Browns, Nagy said. Fields said he believes he is ready for his first NFL start. Dalton suffered the knee injury Sunday against the Cincinnati Bengals after landing awkwardly on the Chicago sideline following a scramble. Dalton's left knee appeared to buckle, and he immediately pointed to Fields to enter the game and headed to the blue injury tent to be examined. Dalton initially appeared to check out OK and reentered the game for a series before going back to the locker room before halftime and later being ruled out. Nagy reiterated Wednesday that Dalton would be the Bears' starter once he is healthy enough to play. Fields went 6 for 13 passing for 60 yards with an interception and rushed 10 times for 31 yards against the Bengals. He threw two passes, both completions, in a Week 1 loss to the Los Angeles Rams.