Fields back in the bullpen mix for Astros

Right-hander joins dominant relief corps

"Josh Fields is a real weapon in the 'pen anytime during the game," Astros manager A.J. Hinch said. (AP)OAKLAND -- Reliever Josh Fields joined the Astros on Friday after recovering from a strained groin he sustained near the end of Spring Training. In a corresponding move, which was announced by the team Wednesday night, Houston optioned infielder Jonathan Villar to Triple-A Fresno.

Fields, who posted a 4.45 ERA in 54 2/3 innings for the Astros last season, allowed two runs in six innings of rehab work with Fresno. The right-hander threw 36 pitches while recording two scoreless innings on Monday in his final outing with the Grizzlies. It was a lengthy…