When Michael Strahan joined "Live! With Kelly and Michael" in September 2012, he was merely a former New York Giants defensive end and NFL commentator. Now, he's officially a television star, and ABC announced Tuesday that he's taking his talents to the morning show big leagues — "Good Morning America."

Strahan already had a contributor role on "GMA," which he started two years ago when ABC wanted to add another shot of testosterone after Josh Elliott's departure to NBC. Now Strahan, who has effortlessly expanded his brand to become an award show host and "Magic Mike XXL" actor and sitcom guest star, will officially leave Kelly Ripa and the popular daytime talk show to join the "GMA" team as a full-time co-anchor in September.

"Michael has been a stellar addition to the broadcast. Over the past two years on 'GMA,' he's proven to be a tireless and versatile broadcaster with an incredible ability to connect with people, from veterans to American pop culture icons and newsmakers," ABC News president James Goldston said. "At 'GMA,' he'll now have even more opportunities to tell stories that inspire, inform and empower people."

The reason "GMA" hired Strahan is clear: Ratings. All "GMA" wants to do is beat "Today," which used to be the most-watched morning show in the country. In late 2012, after "Today" briefly imploded following the forced exit of Ann Curry, "GMA" won in total viewers and has been holding on to the trophy ever since. Many cite the easy chemistry among anchors George Stephanopoulos, Robin Roberts and Lara Spencer as an important element to its success. Season to date, "GMA" is averaging about 5 million viewers per morning, more than the 4.7 million for "Today." 

However, there are signs of trouble. "GMA" has slipped behind in the coveted 25-to-54-year-old demographic, the most important age bracket among advertisers, with only 1.69 million viewers compared to the NBC show's 1.83 million.

(In comparison to last year, both shows are down: During the same time period in the 2014-2015 TV season, "GMA" averaged 5.5 million total viewers and 2 million in the 25-to-54 demo; "Today" had 4.9 million total viewers and 1.9 million in the demo.)

So ABC is hoping to lure more viewers with Strahan, who has become a fan favorite since he replaced Regis Philbin on "Live!" in 2012. Previously, he had guest-hosted "Live!" about 20 times, and his entertaining banter with Ripa made the choice a no-brainer. Plus, he'll breakdance if the occasion calls for it:

Ripa and Strahan turned out to be a dynamic duo, and the pair won a Daytime Emmy last year for outstanding entertainment talk show hosts. The show, distributed by Disney-ABC Domestic Television and already renewed through 2020, ranks second out of all syndicated daytime talkers, only behind the juggernaut "Dr. Phil."

Now that Strahan's gone, you know what that means: More tryouts for "Live!" Prior to Strahan joining the show, Ripa (a co-host since 2001) had a rotating cast of guest hosts eager for the spot. We have a while, given that Strahan isn't expected to decamp to "GMA" until the fall.

"My time with 'Live! with Kelly and Michael' has been transformative, and my departure will be bittersweet," Strahan said in a statement. "Kelly has been an unbelievable partner, and I am so thankful to her and the entire team."

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