Ayers tallied 34.5 sacks in nine NFL seasons, spending the first five years of his career with the Broncos.
Former Broncos, Giants and Buccaneers defensive end Robert Ayers announced his retirement from the NFL on Tuesday.
Ayers last played in 2017, appearing in 12 games with Tampa Bay.
"That's all folks, so thankful," Ayers wrote on Twitter. "Was a helluva run NFL but the time has come. On to the next chapter of life."
The Tennessee product was drafted by the Broncos with the No. 18 pick in the 2009 NFL draft. Ayers spent five seasons in Denver before joining the Giants in 2014.
Ayers recorded a career-high nine sacks with New York in 2015. He played for the Giants in 2014 and 2015, then finished his career with the Buccanneers in 2016 and 2017.
Ayers retires with 34.5 career sacks and 270 tackles.