Cubs pitcher Cole Hamels

Cubs starting pitcher Cole Hamels prepares to throw to home plate in the fourth inning against the Dodgers on April 24, 2019, at Wrigley Field.

Cubs starting pitcher Cole Hamels gestures to the bench after getting hit during the fifth inning against the Marlins on May 6, 2019, at Wrigley Field.

Cubs starting pitcher Cole Hamels walks to the dugout after pitching the first inning against the Marlins on May 6, 2019, at Wrigley Field.

Cubs starting pitcher Cole Hamels delivers to the plate during the first inning against the Marlins on May 6, 2019, at Wrigley Field.

Cubs pitcher Cole Hamels gives a thumbs-up to a fan before a game against the Brewers on May 10, 2019, at Wrigley Field.

Cole Hamels throws in the rain during Cubs spring training at Sloan Park on Feb. 22, 2019, in Mesa, Ariz.

Cubs starting pitchers Cole Hamels and Yu Darvish talk during spring training on Feb. 15, 2019, in Mesa, Ariz.

Cole Hamels warms up his hand while throwing in the rain during Cubs spring training on Feb. 22, 2019, in Mesa, Ariz.

Cubs starting pitcher Cole Hamels plays catch at spring training Feb. 12, 2019, in Mesa, Ariz.

Cubs starting pitcher Cole Hamels warms up during spring training, Feb. 13, 2019, in Mesa, Ariz.

Cubs starting pitcher Cole Hamels in the dugout Aug. 2, 2018, at Wrigley Field.

Cubs starting pitcher Cole Hamels delivers to the plate against the Mets at Wrigley Field on Aug. 28, 2018.

Cubs starting pitcher Cole Hamels delivers in the sixth inning against the Pirates on Aug. 1, 2018, in Pittsburgh.

Cubs pitcher Cole Hamels watches from the dugout during a game against the Royals at Kauffman Stadium on Aug. 6, 2018, in Kansas City

Cubs starting pitcher Cole Hamels heads to the dugout after throwing against the Reds at Wrigley Field on Aug. 23, 2018.

Cubs starting pitcher Cole Hamels stands on the mound before facing the Mets at Wrigley Field on Aug. 28, 2018.

Cubs pitcher Cole Hamels looks on from the dugout against the Cardinals during the second inning at Busch Stadium on July 29, 2018 in St. Louis.

Cubs starting pitcher Cole Hamels, left, and first baseman Anthony Rizzo take the field against the Reds at Wrigley Field on Aug. 23, 2018.

Cubs starting pitcher Cole Hamels looks on from the dugout during a game against the Nationals at Wrigley Field on Aug. 12, 2018.

Cubs pitcher Cole Hamels delivers a pitch against the Nationals at Wrigley Field on Aug. 12, 2018.

Cubs pitcher Cole Hamels delivers against the Brewers on Sept. 3, 2018, in Milwaukee.