After nine years in the NFL, Brandon Jacobs is calling it a career. An hour ago, Jacobs hopped on Twitter to let his followers know that he will be hanging up his cleats for good. Recently, Jacobs underwent cartilage graft surgery where he received new knee cartilage from a 16-year-old boy who died in a car crash. Given the rarity of the procedure (only two doctors in the United States have performed it), Jacobs needed to seriously weigh the pros and cons that went with going through the rigors of another NFL season. In the end, Jacobs decided to call it quits and you can check out his entire post below. 

After 9 years in this whirlwind business they call the NFL, I am proud to announce that I am hanging up my cleats. I've had an amazing run and I appreciate all of the support from the fans through the good and the bad. The New York Giants are a great organization and I am proud to have been a part of it for so long. I love my coaches and my teammates and will miss them as well as the game itself but I am healing well from my surgery and I look forward to running around with my kids for years to come!

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[via Brandon Jacobs]