McGarrahan was originally drafted by the Packers in the sixth round of the 1999 NFL draft. He spent three seasons in Green Bay before getting released in the team's final cutdown in 2001. He subsequently signed on with the Miami Dolphins where he played in 30 of 32 regular season games in the last two seasons.
"As soon as I stepped off the plane, it felt like I was back home," McGarrahan said after practice this afternoon.
McGarrahan, 29, is expected to play in Green Bay's exhibition finale this Thursday against the Tennessee Titans at Lambeau Field. In the meantime he'll be re-familiarizing himself with the Packers defense.
"He's a very good special teams player," said Packers coach Mike Sherman. "He also has to be able to perform as a safety and learn the defense in a very short period of time. He has quite a challenge. I just reminded him of that. It's more than just special teams."
Ironically, McGarrahan got his first sack of his career last Nov. 4 when he dumped quarterback Brett Favre for a 13-yard loss at Lambeau Field.
"It's kind of funny, when I was here, you never even get close to even touching him," McGarrahan said. "Getting a sack was kind of funny."