Willis, who was named to the Pro Bowl in his first seven seasons along with five first-team All-Pro nods, played in just six games in 2014. It was a career low, thanks to a nagging toe injury that required season-ending surgery in November.
He officially announced his retirement Tuesday.
"Patrick epitomizes everything you could ever want in a San Francisco 49er," CEO Jed York said in a statement. "What he brought to this team goes much further than his athletic abilities. His leadership and infectious love for the game helped propel this team. I consider myself very lucky to have grown up around some of the greatest players in the history of this franchise, and Patrick has certainly secured his place among that elite group of men. As a member of our family, Patrick holds a special place in our hearts, and we look forward to supporting him as he moves on from his playing career."
Recently Willis had taken to social media, posting a number of cryptic and religious messages. Bay Area Sport Guys is reporting Willis is going through a religious awakening leading to his decision.
It's not the first time something like this has happened to the 49ers. Former backup running back Glen Coffee retired with religious aspirations just before his second NFL season in the summer of 2010.
Prior to 2014, Willis, 30, never appeared in fewer than 13 games. He has dealt with toe, hand and groin injuries throughout his career and has only played one full season since 2009. After a strong rookie season replacing Willis in the starting lineup, it appears Chris Borland is primed for a starting role along side NaVorro Bowman, who missed all of last season recovering from an ACL tear.
"I’m going to fight and go until I can’t anymore," Willis said after electing surgery. "When I hurt it at the Rams game it kind of made me a little nervous then because I knew what I knew what I had already been feeling all these years. I feel like the Lord was talking to me. I feel like he had finally said, ‘The time is now.’ I feel like everything really happens for a reason. For Chris to come and be playing the way that he was the has the last few games, my replacement, let me start off by first saying that I’m truly proud of the way he’s playing. Whether I was coming back or not, to see him go back out there and hold down that position, as I was trying to do for NaVorro.
In a matter of months, the 49ers team that had gone to three straight conference title games and played in a Super Bowl, will have lost Willis, Frank Gore and its head coach Jim Harbaugh. To pile on, it appears less and less likely former All-Pro defensive end Justin Smith will return to play a 15th season, according to CSN Bay Area.
Willis has two years and nearly $18 million remaining on his contract. A press conference has been called for noon Tuesday.