Nall was originally an undrafted free agent by the Bears in 2018 and he spent his entire rookie year on the practice squad. The former Oregon State running back appeared in 8 games in 2019, mostly on special teams (3 tackles), but he did get some brief offensive action during the week 17 contest that year with 2 carries for 8 yards.
In 2020 he was on the active roster all season long, and in 16 games he had 8 catches for 67 yards, and his first career touchdown, he also had 3 rushes for 0 yards, and he added 4 tackles in the third phase. He played on 65% of their special teams snaps, but just 6% of the snaps on offense.
Nall will be competing for a backup running back spot with 2020 UDFA Artavis Pierce, but I would expect them to bring in at least one other back for competition. David Montgomery and Tarik Cohen are also currently signed for the 2021 season.