He will debut on Monday for Game 3 of the American League Championship Series between the Blue Jays and Royals at 7 p.m ET, assisting with pregame coverage on FOX Sports 1, with game time at 8 p.m.
"I am honored to be a member of the FOX Sports team and excited to have this opportunity," Rodriguez said in a statement. "When I'm not playing baseball, I'm either talking baseball or watching baseball, and I love watching the guys on FOX cover the biggest games in our sport."
The hiring was announced on Sunday as part of the "FOX NFL Sunday" pregame show. Rodriguez appeared on the program and tested his old high school quarterback skills, firing a football past insider Jay Glazer that shattered a TV screen.
"Alex, you know that comes out of your check at FOX," host Curt Menifee quipped.
Rodriguez said on the program that he would not count out the Blue Jays, who trail the Royals, 2-0, in the series heading into Game 3.
"Anyone who writes them off is making a mistake," Rodriguez said. "Trust me, I played against these guys just a few weeks ago. They have the power and they have the pitching. They are going back to Toronto. They are relentless."
The hiring completes a remarkable turnaround for Rodriguez, who engaged in several litigious battles before finally accepting a historic 162-game drug suspension that cost him the 2014 season. He batted .250 with 33 homers and 86 RBIs in 151 games this year.
In June, the 40-year-old became the 29th member of the 3,000-hit club with a solo homer -- the third player to achieve the feat via the long ball. A-Rod also passed Willie Mays for sole possession of fourth place on the all-time homer list in May, finishing the season with 687 homers -- 27 shy of tying Babe Ruth for third place.
Rodriguez will join host Kevin Burkhardt and analysts Raul Ibanez, Pete Rose and Hall of Famer Frank Thomas in FOX Sports' Los Angeles studio for the ALCS and on-site at the World Series.
"Alex has always impressed us from afar with his ability to articulate the game extraordinarily well," said John Entz, president of production at FOX Sports. "In meeting with him, it was obvious he has strong recall when it comes to information, a great familiarity with the remaining teams in the field, and we have no doubt that he'll be an excellent fit with our guys."