Fulmer was 0-2 with an 8.49 ERA in eight games and was sent to Triple-A Charlotte. He was the eighth overall pick in the 2015 draft and is one of the team's best prospects.
Ranaudo will come up from Charlotte to make his second start for Chicago. He allowed three runs in 6 2/3 innings in a loss against the Cubs on July 27.
Ranaudo was acquired from Texas in May and is 1-1 with an 8.71 ERA in three games.