Falcons coach Dan Quinn confirmed the news during his Tuesday news conference.
Although the Falcons are unsettled at the backup quarterback position behind Matt Ryan, Quinn would not commit to signing Grossman immediately. Current backups T.J. Yates and Sean Renfree have been battling for the No. 2 role this preseason, but both have underwhelmed.
"I think, just like at every position, we're happy with the two guys we have, but when there's a time to come work out somebody and see where he's at or so where the player is at or how we can help improve, we're going to look at that every chance we get," Quinn said. "Wouldn't look too much into that other than that's another opportunity for us to do that."
Quinn was pressed on whether he was truly content with Yates and Renfree, considering the team brought in an experienced veteran such as Grossman.
"I think so, yeah," Quinn responded. "If there's a way to say, 'OK, can we still compete and battle for it to improve in a little way?' then we'll still try to do that. I think it's at all the spots, whether it be any of them."
Grossman, who turned 35 on Sunday, has familiarity with the scheme. He played under Falcons offensive coordinator Kyle Shanahan in both Washington and last year for a short training camp stint with Cleveland. The Browns attempted to bring Grossman back during the regular season following injuries to Brian Hoyer and Johnny Manziel, but Grossman declined the invitation.
Back in June, Shanahan shared his thoughts about what he liked about Grossman in Washington.
"I loved Rex because he was so tough. Rex would hang in there, get the crap knocked out of him every week," Shanahan said. "He never flinched. He'd hang in there and take all the hits. He didn't mind the pressure on him. He'd let it sling every time. Sometimes, I'd have to tell Rex that he was letting it sling around a little too much and that you might have to take a sack here or throw it away. But the thing I loved about Rex is how much he competed. Every time that he was in the game, I felt like we had a chance. If he was going to throw three picks, I felt like there was a great chance he was going to come back and throw three touchdowns. He was a real fun guy to have."