Brothers are born to fight. From the Bible to this year’s Super Bowl matchup, where 49ers coach Jim Harbaugh will face off against brother John Harbaugh, head coach of the Baltimore Ravens, brothers have been battling throughout history.
Take a look at some of the top brothers clashes that have taken place with the sports world watching. Keep in mind, we're only including brothers who compete head-to-head on the field, court, or sidelines in the case of opposing coaches.
So sorry, Peyton and Eli, and Pedro and Ramon. You don't make the cut. Next
Boston Bruins legend Phil Esposito and his brother, Tony, are among the greatest players in hockey history. Phil was traded to the Bruins in 1967, while Tony is best remembered for his time as the Chicago Blackhawks goalie. Both were All-Stars, and both were inducted into the Hockey Hall of Fame, Phil in 1984 and Tony in 1988. Next
It seems like everybody is related in NASCAR. Joking aside, there are numerous brothers who race against one another, like Kyle and Kurt Busch. It hasn't always been an easy road for the Busch brothers though. In 2007, while racing for a million-dollar prize in the all-star race, Kyle dove below Kurt in an attempt to make a pass. Both cars wrecked and the bad blood stayed between them for some time.
They eventually reconciled, but both are extra wary of the other during races.
Other racing brothers through the years include Bobby and Terry Labonte, Jeff and Ward Burton, Geoff and Todd Bodine, and Bobby and Donnie Allison. Next
Dueling brothers are part of the high school sports scene, too. When Weymouth High School and Walpole High School go head-to-head in football, so do twin brothers Brian and Barry Greener. Brian coaches Weymouth while Barry is coach at Walpole. This season, in the last game of the regular season, Walpole defeated Weymouth 48-21. Next
Former MLB brothers George and Ken Brett became teammates, but only after they spent years on separate ball clubs. George spent his entire 21-year career with the Kansas City Royals while Ken jumped around from the Red Sox and White Sox to the Dodgers and Phillies. George played third base and was a designated hitter, while Ken pitched.
George had 20 plate appearances vs. Ken, and had six hits and 1 RBI, including a pair of doubles. Next
The Sutter family was one of the largest and most successful hockey families to play in the NHL. Brian, Darryl (pictured), Duane, Brent, Rich, and Ron all played in the NHL and together, there was a Sutter brother in the league every year from 1976-2001.
Naturally, countless head-to-head battles ensued. Next
The Lopez twins
Standing at a towering seven feet are the Lopez twins, Brook (pictured) and Robin, who play in the NBA. Straight out of Stanford in 2008, Brook and Robin were first-round draft picks. Brook was drafted 10th by New Jersey (now the Brooklyn Nets) while Robin followed shortly, picked 15th by the Phoenix Suns (he now plays for the New Orleans Hornets).
Brook and Robin both play center, and the next time they will face each other is Feb. 26 in New Orleans. Next
Also in the NBA are brothers Pau and Marc Gasol. Older brother, Pau, has 11 years of NBA experience and currently plays for the Los Angeles Lakers. Baby brother Marc is in his fifth year with the Memphis Grizzlies. The last time the two teams met, in November, the Grizzlies beat the Lakers 106-98.
The two did team up in the Olympics, helping Spain to the gold-medal game, where it lost to the United States. Next
As if a "Har-Bowl" wasn't enough for the NFL, let's take a moment to look at Rex and Rob Ryan. Rob Ryan was the Dallas Cowboys' defensive coordinator through the 2012 season, but was fired after the Cowboys failed to make the playoffs.
More famously, or infamously in New England, Rex Ryan is the New York Jets head coach, a rival the Patriots have encountered on numerous occasions. The last time the twins' teams met, in 2011, the Cowboys lost a close 27-24 game. Next
Eric, Marc, Jordan and Jared Staal all have something in common: hockey. Eldest brother Eric plays for the Carolina Hurricanes along with younger brother Jordan, who joined the Hurricanes this year after six years with the Pittsburgh Penguins. Marc is now in his sixth season with the New York Rangers.
The youngest brother, Jared has played in the AHL for various teams since joining the league in 2005. Next
The Williams sisters
We know, we know. Venus and Serena aren't brothers. But when it comes to sibling rivalry on the courts, you can't deny that these two sisters are fiercely competitive. They've played each other in Grand Slam events 12 times, and Serena holds a 13-10 edge in career showdowns at WTA Tour events.
Serena has 47 career victories, while Venus has 44. Next
Older ski racing fans will remember the Mahres as the faces of US skiing in the 1970s and 80s. Phil won silver in the slalom at the 1980 Olympics at Lake Placid, and then Phil edged Steve for the gold in the 1984 Olympic slalom in Yugoslavia.
The two were fixtures on the World Cup circuit as well, and Phil Mahre won three straight World Cup titles from 1981 to 1983.
In the photo, Phil is at left, followed by fellow Olympic skiers Heidi Voelker, Steve Mahre, Tommy Moe, and Stein Eriksen.
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