Garcia was sent down Monday, an off day for the team before it opens a three-game series at Cincinnati on Tuesday. That's when Nicasio is expected to be reinstated.
The right-hander has been on the DL since Aug. 10 with a left abdominal strain. He is 1-3 with one save and a 3.06 ERA in 38 games.
Garcia is 3-3 with one save and a 3.55 ERA in 46 games in three stints with the Dodgers this season.