The Cubs moved up the start of their game against the Rays on Wednesday to 5:30 p.m. due to rain in the forecast later in the evening.
The Rays are not scheduled to come back to Wrigley Field this season, which would complicate rescheduling a rainout.
The series finale was originally scheduled for 6:40 Wednesday. No ticket exchange is necessary for fans attending the game. Gates are set to open at 4:30 p.m.
The three-game series is tied at one apiece entering play Wednesday, with right-hander Marcus Stroman scheduled to take the mound for the Cubs.