The Canada international played a full 90 minutes in the Reds 2-0 loss to LA Galaxy in California, his first match in just over two months, and was happy to have put in a full shift.
"I was able to survive 90 minutes," de Guzman said.
"There was a point where I cramped up but now I'm recovered and ready to go again.
"In a way, I feel like I came out of retirement. But I'm happy to be back and looking forward to this whole journey with TFC."
Following the debut, the 28-year old now has his sights set on helping his new team make the MLS play-offs.
"It's clear now that every game ahead of us is pretty much like a (cup) final," he added.
"It's a difficult situation but it's still possible and the guys are still motivated."