CHICAGO -- Monday night’s series opener between the White Sox and Nationals at Guaranteed Rate Field was postponed due to rain.

The rain started to fall in Chicago shortly after White Sox pregame batting practice began and was in the forecast through early Tuesday afternoon.

“My radar says we’re in a little bit of trouble,” White Sox manager Pedro Grifol said before the game about the chance to play Monday. “But I’m not the expert here.”

A straight doubleheader will be played Tuesday, prior to Wednesday afternoon’s series finale, with Game 1 beginning at 3:40 p.m. CT (4:40 p.m. ET). The second game will start approximately 30 to 45 minutes following the conclusion of the opener.

Fans with tickets, parking and Huntington Bank Stadium Club passes to the originally scheduled 6:40 p.m. CT contest on May 14 can attend both games of the doubleheader. Season ticket holders, individual suite holders and patio ticket holders will receive a credit to their account for game tickets and parking for the postponed game on May 13. Refunds for all other purchases, including Ticketmaster, SeatGeek and Stubhub, should be initiated at the point of purchase.

After being scheduled to start Monday’s contest for the White Sox, Chris Flexen will get Game 1 of the doubleheader on Tuesday. Erick Fedde, who posted a 5.41 ERA over 102 games (88 starts) during six seasons with the Nationals from 2017-22, starts Game 2. Fedde has a 3-0 mark with a 3.00 ERA in his first year with the White Sox.

Trevor Williams, who was slated to start Monday for the Nationals, will pitch Game 1 on Tuesday. Mitchell Parker, who was set to start Tuesday before Monday’s rainout, will start Game 2.