Frank Gore and Joe Staley could not have come from much different backgrounds.
But during the course of their eight seasons together with the 49ers -- and in the years that followed -- they grew tight as they discovered a lot of commonalities.
Gore entered the NFL two years before Staley, who announced his retirement Saturday after 13 NFL seasons.
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Gore remains a free agent. He is looking to play a 16th NFL season. He ranks third all-time behind Emmitt Smith and Walter Payton with 15,347 rushing yards.
Staley helped Gore reach his status as one of the top running backs in NFL history.
Gore and Staley are forever linked. Both players were recently chosen for the NFL All-Decade team of the 2010s. Both share an infectious love of the sport. Staley calls Gore “a great ambassador for the game.” The same could certainly be said about Staley.
“I think he knows now because I communicated this with him, but I don't think at the moment he understood how much of an impact he had on my football career,” Staley said of Gore.
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Gore, who grew up in the rough Miami neighborhood of Coconut Grove, was a highly recruited running back at the University of Miami, where he was considered every bit the star as Clinton Portis and Willis McGahee. But Gore had an injury-plagued college career and entered the NFL as a third-round draft pick of the 49ers in 2005.
He rushed for a career-best 1,695 yards in his second season.
Staley accepted his only scholarship offer to attend Central Michigan, 70 miles from his hometown of Rockford, Michigan.
He had no realistic thoughts of playing professional football until he was converted from tight end to offensive tackle and excelled. The 49ers moved up in the first round to select Staley with the 28th pick of the 2007 draft.
“Frank was a guy that I watched,” Staley said. “I was a huge sports fan growing up, and he was a guy that I watched and not idolized, but he was a superstar. So I came in the NFL, and he had just got done rushing for 1,600 yards, and he was a guy that was the leader of the team and he was a San Francisco 49er.
“To watch him work and the way that he approached every single day was special for me as a rookie just being like ‘This is what it takes to be a stud in the NFL.’ ”
[RELATED: Joe Staley happy 49ers got Trent Williams trade done during NFL draft]
Staley was leaning toward retirement for the past month due to long-term health concerns, including a troublesome neck condition. Hours after the 49ers acquired seven-time Pro Bowl left tackle Trent Williams in a trade from Washington, Staley publicly announced his retirement.
Gore reached out to Staley a short time later.
“It was a special conversation just to be able to talk with him,” Staley said. “He shared some nice words and stuff like that. He’ll be a lifelong friend and someone I was very fortunate enough to cross paths with for a long time and have a lot of special moments with.”