Sage Rosenfels announced his retirement from the NFL on Sunday night, admitting it was a decision that was made more by the league’s 32 teams than him.

Adam Caplan of the Sideline View picked up on the announcement first. Rosenfels, 35, played for five different organizations and was last a backup for the Minnesota Vikings in 2011. Originally drafted by the Washington Redskins, Rosenfels also played for the Miami Dolphins, Houston Texans and New York Giants. He appeared in 44 games and made 12 starts, going 6-6. Rosenfels had a 4-1 record as a fill-in starter for the Texans in 2007.

Rosenfels left a long and meaningful note on his Facebook page in explaining the decision. He even thanked a sports writer.

“I always knew the day would come,” he wrote. “I just didn’t think I’d be 35 when it finally happened. I will soon be turning in my paperwork to the NFL and formally retiring after a 12 year career. Like most NFL players, I wish I could have played a couple more seasons, but usually the league is done with you before you are done with it.

“It definitely was a roller coaster ride with many ups and downs and not a lot of years where I felt comfortable with my standing on a team. A dozen years of battling every day to make it another year and to prove myself against some of the best athletes in the world.”

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Brad Biggs covers the Bears for the Chicago Tribune