Chapman will be shut down with no throwing for two weeks and likely will be sidelined for a month or more, Yankees general manager Brian Cashman said.

An MRI exam on Saturday showed the extent of the injury for the 29-year-old Cuban-born left-hander, who had struggled in his past two outings.

Chapman surrendered three hits and a run in two-thirds of an inning in a 5-1 home loss to Houston on Friday. A week ago, he squandered a three-run lead in the ninth inning against the Chicago Cubs in a game the Yankees eventually won after 18 innings.

After starting last season with the Yankees, Chapman was traded to the Cubs in July and wound up playing a crucial role in the team's run to the World Series title, the Cubs' first since 1908.

With the Cubs down 3-1 to Cleveland in the best-of-seven final, Chapman allowed only one hit over the last three innings in Chicago's 3-2 win in game five and just one hit and one run in the last inning of Chicago's 9-3 victory in game six.

Chapman was the winning pitcher in the decisive seventh game despite surrendering a run to Cleveland that forced extra innings, becoming a World Series winner for the first time.

After the season, Chapman returned to the Yankees, signing a five-year deal worth $85 million dollars (77 million euros). So far this season, he has a 3.55 earned-run average with 21 strikeouts over 12 2/3 innings in 14 appearances.

Chapman made a record 49 consecutive relief appearances with at least one strikeout in 2013 and 2014 and owns the fastest record pitch in major league history at 105.1 mph (169km/h).

At 22-12, the Yankees lead the American League East division and own the third-best record in the major leagues after Houston and National League leader Washington.