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Main photo: Al Messerschmidt/Getty Images; Insert: Al Kooistra/Getty Images
Tiger Woods: Oakland Raiders While Tiger's NBA fidelity has been called into question (he professes loyalty to the Lakers but is a regular and enthusiastic Magic fan), he has remained steadfast in his support of the Oakland Raiders, who played in Los Angeles when Tiger was growing up in Southern California.
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Main photo: Shawn Dowd/Getty Images; Insert: Paul Spinelli/AP
Phil Mickelson: San Diego ChargersFootball nut Mickelson probably knows more about your team than you do, but his favorite NFL squad is his hometown San Diego Chargers. Waiting on the tee at the 2009 U.S. Open at Bethpage, Mickelson even called out to a spectator wearing Chargers gear: "Nice sweatshirt, man," Mickelson said.
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Mahan: Fred Vuich/SI; Harris: Damian Strohmeyer/SI
Hunter Mahan: Dallas CowboysA longtime Dallas-area resident and avid sports fan, Hunter Mahan is solidly in the Cowboys camp. Of course, if you married a Cowboys cheerleader like Mahan did [Kandi (Harris) Mahan, pictured], you'd probably be a Cowboys fan too.
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Doug Benc/Getty Images
Jack Nicklaus: Miami DolphinsNicklaus (pictured with Dan Marino, center, and Drew Brees) has been a Dolphins season ticket holder since 1966, and he doesn't travel on weekends during football season. Growing up in Columbus, Ohio, Nicklaus considered playing football for Ohio State, but legendary coach and family friend Woody Hayes told Nicklaus's dad Charlie that, "He's got a real future in the game of golf. If he was my son, and if I was going to offer some advice: I'd keep him as far away from my game as I could."
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Main photo: Gene J. Puskar/AP
Arnold Palmer: Pittsburgh SteelersBorn in Steeler Country (Latrobe, Pa.), Palmer has been a fan of the franchise since almost the beginning and he was a close friend of Steelers founder Art Rooney. "I knew him very well," Palmer told Steelers.com. "He was the inspiration behind the start of the Steelers and carried it right on until his death."
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Main photo: Angus Murray; Insert: Al Bello/Getty Images
Rory McIlroy: New York JetsMcIlroy's real football team is Manchester United, but McIlroy follows American football too. "If I had to follow a team it would be the Jets, but I just enjoy following NFL," McIlroy tweeted in December 2010.
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Main photo: Kohjiro Kinno/SI; Insert: Scott Boehm/Getty Images
Steve Stricker: Chicago BearsThe Upper Midwest is a strange place when it comes to fan loyalty. Take Steve Stricker: the pride of Wisconsin is actually a Bears fan. The Milwaukee Journal Sentinel's Gary D'Amato explains: "Steve Stricker is a University of Illinois graduate, but he is a huge fan of the University of Wisconsin. He grew up in Edgerton, Wis., in the middle of Green Bay Packers country, but is a longtime fan of the Chicago Bears."
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Main photo: Hunter Martin/Getty Images; Insert: Rhona Wise/Bloomberg via Getty Images
Brad Faxon: New England PatriotsA Rhode Island native, Faxon is a huge fan of the Boston sports scene. Once the golf season is over, Faxon regularly attends Patriots home games and often tweets about the team.
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Frank Micelotta/Getty Images
Jim Furyk: Pittsburgh SteelersFuryk lived in Western Pennsylvania as a child and has remained a lifelong Steelers fan. If you think Furyk's backward-turned hat celebration at the 2010 Tour Championship was intense, it's nothing compared to what happens during a tense Ravens-Steelers game: "I scare my kids once in a while at home watching the Steelers," Furyk told Golf Magazine.
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Main photo: Phelan M. Ebenhack/AP; Insert: David Sherman/Getty Images
Tim Herron: Minnesota VikingsNo surprise that the only Minnesota native on the PGA Tour loves the Vikings. Sometimes you can even find Herron watching a Vikings game while ice fishing. It doesn't get any more Minnesota than that.
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Main photo: Carlos M. Saavedra/SI; Insert: Drew Hallowell/Getty Images
Sean O'Hair: Philadelphia EaglesWhen on Tour, O'Hair is always hungry for news about his Eagles and Phillies. O'Hair, who lives in the Philly suburbs, was treated like a hometown hero when the PGA Tour returned to Philadelphia for the AT&T National.