McGwire has never been a bench coach, but he has experience on a big league staff. He spent the last three seasons as the Dodgers' hitting coach before his contract expired at the end of October. McGwire previously was the hitting coach for the Cardinals for three years (2010-12) before joining the Dodgers.
A native of Pomona, McGwire starred at USC before embarking on a 16-year big league career with the A's and the Cardinals. He hit 583 home runs, including 70 during the 1998 season.
The Padres have a first-year manager in Andy Green, but have not officially announced any other additions to the coaching staff -- though pitching coach Darren Balsley and third-base coach Glenn Hoffman are returning.
Last week, Astros assistant hitting coach Alan Zinter was hired as the Padres' hitting coach, sources told MLB.com's Corey Brock. Tarrik Brock will coach first base and former Padres pitcher Doug Bochtler will be the bullpen coach.
"You always want to have guys who complement your [manager's] skill set. I don't look at it where it has to be someone who has to fit three or four experienced criteria, guys who have managed or coached before," said Padres general manager A.J. Preller last month.
Austin Laymance is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.