Cubs starting pitcher Yu Darvish

Cubs starting pitcher Yu Darvish returns to the dugout after the fourth inning against the Diamondbacks on April 20, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish gets a new ball after giving up a home run against the Diamondbacks on April 20, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish prepares to take the field against the Diamondbacks on April 20, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish delivers to the plate against the Pirates in the second inning April 10, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish heads to the locker room after being pulled from the game in the sixth inning against the Pirates on April 10, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish delivers to the plate against the Pirates on April 10, 2019, at Wrigley Field.

Cubs starting pitcher Yu Darvish stands on the mound in the first inning of a spring training game against the Diamondbacks on Feb. 26, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish delivers to the plate in the second inning of a spring training game against the Diamondbacks on Feb. 26, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish throws during spring training Feb. 13, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish stretches during spring training on Feb. 13, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish stretches against a wall during spring training Feb. 17, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish throws during spring training Feb. 12, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish runs in the rain during spring training on Feb. 18, 2019, in Mesa, Ariz.

Cubs starting pitcher Yu Darvish during spring training on Feb. 15, 2019, in Mesa, Ariz.

Cubs pitcher Yu Darvish warms up during spring training on Feb. 13, 2019, in Mesa, Ariz.

Cubs pitcher Yu Darvish warms up during spring training on Feb. 22, 2019, in Mesa, Ariz.

Yu Darvish walks between fields during Cubs spring training on Feb. 19, 2019, in Mesa, Ariz.

Cubs pitcher Yu Darvish relaxes in the media room during the opening day of the annual Cubs Convention at the Sheraton Grand Chicago, on Friday, January 18, 2019. (Chris Sweda/Chicago Tribune)  (Chris Sweda / Chicago Tribune)

Yu Darvish pitches the first inning for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish pitches the first inning for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish pitches the first inning for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish in the dugout before pitching for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish warms up in the bullpen before pitching for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish warms up before pitching for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish speaks the media after pitching one inning for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Yu Darvish shakes his arm after pitching the first inning for the South Bend Cubs in a rehab start Aug. 19, 2018, at Four Winds Field.

Cubs head trainer PJ Mainville watches Yu Darvish workout in left field before a game at Wrigley Field on July 19, 2018.

Cubs starting pitcher Yu Darvish in the dugout on July 1, 2018 at Wrigley Field.

Yu Darvish delivers a pitch against the West Michigan Whitecaps during the fourth inning at Four Winds Field in South Bend, Ind. on Monday, June 25, 2018.

Yu Darvish warms up for the South Bend Cubs against the West Michigan Whitecaps at Four Winds Field on Monday, June 25, 2018.

Cubs starter Yu Darvish pitches a simulated game Wednesday, June 20, 2018, at Wrigley Field as he recovers from a triceps injury.

Cubs starter Yu Darvish pitches a simulated game Wednesday, June 20, 2018, at Wrigley Field as he recovers from a triceps injury.

Cubs starter Yu Darvish looks out from the dugout during a game against the Phillies at Wrigley Field on Tuesday, June 5, 2018.

Yu Darvish sits with Kyle Hendricks in the Cubs dugout before a game at Wrigley Field against the Giants on May 27, 2018.

Cubs starting pitcher Yu Darvish prepares to throw in the second inning against the Reds on May 20, 2018.

Yu Darvish prepares to take the mound for the game against the Reds at Great American Ball Park on May 20, 2018.

Yu Darvish looks on in the eighth inning against the Reds at Great American Ball Park on May 18, 2018. The Cubs won 8-1.

Yu Darvish walks off the field after pitching in the first inning against the Braves at SunTrust Park on May 15, 2018.

Yu Darvish pitches in the first inning against the Braves at SunTrust Park on May 15, 2018.

Cubs starting pitcher Yu Darvish in the dugout during the game against the White Sox at Wrigley Field on May 13, 2018.

Cubs starter Yu Darvish watches from the dugout during the ninth inning against the Cardinals on Friday, May 4, 2018, in St. Louis.

Cubs starter Yu Darvish (11) adjusts his cap after giving up a two-run home run to Rockies third baseman Nolan Arenado in the first inning at Wrigley Field, Wednesday, May 2, 2018.

Cubs starter Yu Darvish scratches his nose while heading to the dugout before a game against the Rockies at Wrigley Field Wednesday, May 2, 2018.

Cubs starter Yu Darvish pitches against the Brewers at Wrigley Field on April 27, 2018.

Cubs pitcher Yu Darvish gives an interview before a game against the Indians on April 25, 2018, in Cleveland.

Starting pitcher Yu Darvish throws in the first inning against the Rockies at Coors Field on April 21, 2018.

Cubs starting pitcher Yu Darvish during the fourth inning against the Braves on April 13, 2018.

Cubs starter Yu Darvish looks on in the first inning of a game against the Reds at Great American Ball Park in Cincinnati on April 2, 2018.

Cubst starter Yu Darvish attempts a bunt in the fifth inning against the Marlins at Marlins Park on March 29, 2018 in Miami.

Cubst starter Yu Darvish warms up before the first inning against the Marlins at Marlins Park on March 29, 2018 in Miami.

Yu Darvish high-fives teammates in the dugout after the second inning of his spring training debut for the Cubs on March 6, 2018.

Yu Darvish delivers a first inning pitch during a spring training game against the Dodgers on March 6, 2018 in Mesa, Ariz.

Yu Darvish signs autographs at Cubs spring training on Feb. 16, 2018.

Yu Darvish poses during Cubs photo day at spring training on Feb. 20, 2018.

Cubs starting pitcher Yu Darvish runs in the outfield at the team’s spring training baseball facility on Feb. 16, 2018.

Yu Darvish pitches during the second day of Cubs spring training at Sloan Park Thursday Feb. 15, 2018, in Mesa, Ariz.

Yu Darvish watches Justin Grimm do a handstand while warming up during the second day of Cubs spring training at Sloan Park on Feb. 15, 2018.

Yu Darvish pitches during the second day of Cubs spring training at Sloan Park Thursday Feb. 15, 2018, in Mesa, Ariz.

Yu Darvish pitches during the second day of Cubs spring training at Sloan Park Thursday Feb. 15, 2018, in Mesa, Ariz.

Yu Darvish pitches during the second day of Cubs spring training at Sloan Park Thursday Feb. 15, 2018, in Mesa, Ariz. (Armando L. Sanchez/Chicago Tribune)  (Armando L. Sanchez / Chicago Tribune)

Cubs president Theo Epstein puts a jersey on newly signed pitcher Yu Darvish at a spring training press conference on Feb. 13, 2018.

Cubs starting pitcher Yu Darvish takes a break from warmup pitches at the team’s spring training facility Tuesday, Feb. 13, 2018, in Mesa, Ariz.

Newly signed Cubs pitcher Yu Darvish looks at Theo Epstein while attending a press conference at Sloan Park on Feb. 13, 2018, in Mesa, Ariz.

Newly signed Cubs pitcher Yu Darvish arrives at Cubs spring training on Feb. 13, 2018, in Mesa, Ariz.

Dodgers starter Yu Darvish watches from the dugout during the eighth inning of Game 7 of the World Series against the Astros on Wednesday, Nov. 1, 2017, in Los Angeles.

Dodgers starter Yu Darvish walks to the dugout after being relieved during the second inning against the Astros in Game 7 of the World Series at Dodger Stadium in Los Angeles on Nov. 1, 2017.

Dodgers starter Yu Darvish looks to the sky as he leaves Game 3 of the National League Championship Series against the Cubs at Wrigley Field on Tuesday, Oct. 17, 2017.

Dodgers starter Yu Darvish delivers a pitch in the second inning against the Mets on Aug. 4, 2017, at Citi Field in Queens, N.Y.

Rangers pitcher Yu Darvish throws during spring training Friday, Feb. 19, 2016, in Surprise, Ariz.

Rangers pitcher Yu Darvish watches the game from the dugout during the second inning against the Indians at Progressive Field on Aug. 1, 2014, in Cleveland.

Rangers starter Yu Darvish pitches in the first inning against the Mariners at Rangers Ballpark in Arlington, Texas, on Aug. 18, 2013.

Rangers pitcher Yu Darvish stands on the mound at Rangers Ballpark in Arlington, Texas, on Jan. 20, 2012, after signing a six year, $60 million deal.

Japanese pitcher Yu Darvish of Nippon-Ham Fighters shouts during a game against Softbank Hawks in Fukuoka, Japan, on Sept. 17, 2011.

Japanese pitcher Yu Darvish of Nippon-Ham Fighters hurls the ball against Seibu Lions batters in Sapporo, Japan, on Oct. 29, 2011.

Yu Darvish of Japan pitches against Korea during the 2009 World Baseball Classic on March 17, 2009, at Petco Park in San Diego, Calif. (