Pinckney suffered its first two losses in SEC White baseball play Monday, getting swept 9-6 and 11-9 at Chelsea.
The Pirates still control their fate in their quest for the division championship with three games remaining against first-place Adrian.
Adrian also lost for the first time in SEC White play, falling 13-6 to Tecumseh in the first game before winning 12-0 in the nightcap.
Adrian is 7-1, while Pinckney and Chelsea are 6-2 in the division. Pinckney will host Chelsea in a single game at 4:30 p.m. Wednesday and will have its three-game series with Adrian in two weeks.