Both natives of Austin, Texas, Brees and Mayfield have been likened to one another for their smaller statures and passing accuracy.
The two will meet for the first time Sunday when the Saints and Browns square off, though Mayfield is slated to serve as a backup for Tyrod Taylor once again.
"Man, he's got all the tools," Brees said of Mayfield. "He's more athletic. He probably can run around better. He's got a stronger arm."
The 39-year-old Brees added he couldn't help but notice Mayfield in college, where he became one of the most prolific passers in Oklahoma history and captured the Heisman Trophy in 2017.
"I followed his college career," said Brees. "Couldn't have been more impressed with what he was able to accomplish, especially last year. Really impressed with the way he plays the game. I think he's a great competitor."