Rice, 42, signed with the Broncos this summer in hopes of playing a 21st season with a winner. Rice moved ahead of Darius Watts as the team's third receiver before Watts moved ahead of him in last week's game against Indianapolis.
In the preseason finale against Arizona, Rice played more, but that was because the starters were on the bench. Hampered by a nagging foot injury, Rice caught only four passes for 24 yards in the preseason and had trouble getting open.
"I feel like it's time now," Rice said in an interview that aired on ESPNnews Monday. "I came here to compete for that third position. I gave it my best shot and it didn't happen. I did this at the right time. I'm here today to make it official."
Rice holds virtually every receiving record imaginable. Those records include but are not limited to career receptions (1,549), yards receiving (22,895) and touchdowns receiving (197).
The San Francisco 49ers, his team for his first 16 seasons, released him after the 2000 season in large part because the team was rebuilding and had younger receivers such as Terrell Owens ready to become cornerstones.
No more than one day later, the Oakland Raiders signed Rice, who proved to his old team that he was far from finished. When Rice came to Oakland, some people wondered if he could co-exist with Tim Brown, who like Rice with San Francisco was the No. 1 man for the Raiders for so many years.
In four seasons as a Raider, Rice caught 243 passes for 3,286 yards and 18 touchdowns including a Pro Bowl season in 2002 to help the Raiders reach their first Super Bowl in 19 seasons.
Oakland traded Rice to Seattle in after Week 6 of the regular season in 2004 at his request because of his diminished role in then first-year head coach Norv Turner's offense.
"It was real difficult," Rice said of his decision to retire. "I've had this routine for so many years. This has been my livelihood. Now, it's a situation where it's over with. I'm ready for the next stage of my life. I'm going to approach it the same way."
Vince D'Adamo can be reached at firstname.lastname@example.org