"[She] took a sick day," a source tells Us Weekly. "No way she was walking back into that today." A show rep adds: "Kelly had today off from the show."
The former NFL player, 44, was joined on Wednesday by actress Ana Gasteyer, who filled in for Ripa, 45. He thanked Ripa before ending the broadcast.
"I really want to thank, of course, Kelly Ripa," Strahan told the audience. "Kelly welcomed me here, and I've learned so much from her, and she's just been an amazing influence on me. And this has truly changed my life to be here with her. And I know that the show will continue to be strong and great, because with Kelly and Michael Gelman and the staff — everybody here is so talented, and this show has not been around for over 30 years by mistake."
"Kelly, I thank you. I love you. And everyone else here at Live," he continued. "I'm not going to cry on TV, mama. I promise you. But everybody, thank you. Thank you, guys, so much."
As previously reported, Strahan is headed to Good Morning America full-time. "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 on Tuesday. "He will end a four-year run as Kelly Ripa’s cohost on Live, where he has honed his skills as an interviewer with genuine warmth and a quick wit. At GMA, he’ll now have even more opportunities to tell stories that inspire, inform and empower people."
Strahan joined Ripa on the morning talk show in 2012. Ripa, meanwhile, has been a staple on the program since 2002. She originally took over for Kathie Lee Gifford, joining Live vet Regis Philbin at the time.
Strahan opened up about working with Ripa back in February. "Kelly is fun. It doesn’t feel like work. Every day we laugh together," he told FOX411. "Literally, she is my work wife. I am married at work, and I am married to a fun woman, who comes in every day and brings her A-game, and she just celebrated her 15th year of doing this show, which is just amazing to me … For the show to being doing as well as it’s been doing is a testament to her."
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