CLEVELAND -- Guardians pitching coach Carl Willis was released from the hospital Thursday and cleared to rejoin the team.

Willis became lightheaded before Wednesday's series finale against the Colorado Rockies and was taken for tests. The team said the 62-year-old will travel with the Guardians, who open a three-game series in Boston on Friday.

Willis is in his seventh season on manager Terry Francona's staff in Cleveland. He was also with the club from 2003 to 2009.

A former big league pitcher, Willis has been instrumental in helping develop some of Cleveland's top pitchers, including Shane Bieber, the 2020 AL Cy Young Award winner. CC Sabathia (2008) and Cliff Lee (2009) also won Cy Youngs under Willis' tutelage.

Willis appeared in 267 major league games for Minnesota, Cincinnati, Detroit and the Chicago White Sox from 1984-95. He went 22-16 with a 4.25 ERA.