The 42-year-old former NFL star and current co-host with Kelly Ripa of "Live with Kelly and Michael" got a red-carpet welcome from the "GMA" team.
Anchor Robin Roberts expressed excitement that Strahan will be there "a couple of days a week."
The cast then presented him with an alarm clock and a huge coffee cup.
His brief appearance ended with promises he'll be back "next week."
Strahan joins Roberts, George Stephanopoulos, Amy Robach, Lara Spencer and Ginger Zee on the morning show.
Unconfirmed reports of Strahan's new part-time gig surfaced early this month. He has said this side job won't affect his daily duties hosting "Live."