Every athlete who ascends to the professional ranks has done so by dominating at nearly every other level of the sport, and it is understandable that these athletes would accumulate a fair amount of confidence along the way. Athletes who continue to dominate at the professional level have to be particularly competitive and fiery, and sometimes having two athletes who are intent on proving that their confidence is not mere hubris can result in some seriously volatile relationships.

In the early stages of a professional relationship, egos are typically set aside for the good of the team. As time rolls on, however, these egos will eventually get in the way and destroy whatever goodwill has been established among teammates. Sometimes athletes who end up hating each other can remain professional enough to continue to enjoy team success, but most of the time one or the other ends up having to go. In the cases of these 10 pairs of athletes, what began as a promising athletic relationship ultimately devolved into unbridled hate that would destroy the hopes of any future success.

It shouldn’t be surprising that this happens frequently, as professional sports teams are often composed of a group of athletes who are used to being the alpha. Some players are able to adjust to a new and sometimes lesser role, while others refuse to be anything other than the top dog. There have even been some cases in which championship teams have been broken apart simply so that one athlete could prove that he was capable of winning a championship without being the so-called “second-fiddle.” What follows are 10 athletes whose professional relationships deteriorated so much that it turned into absolute hatred.

10 10. Magic Johnson and Kareem Abdul-Jabbar

Abdul-Jabbar, the legendary big man and all-time NBA leading scorer, eventually developed a professional relationship with Magic Johnson, though the foundation on which that relationship was built was not strong enough to last throughout the entirety of their time together in Los Angeles. Abdul-Jabbar and Johnson got along well enough that the Lakers were considered the team of the 80s, winning five championships during a decade many believe to be one of the greatest eras of the sport.

Despite their success, Magic believed that Kareem was slowing the “Showtime” Lakers down, and he openly suggested that it was time for one of the greatest centers of all time to move on. At the heat of the dispute, Johnson told a pair of reporters, “When he leaves, you'll be able to see the real Magic show. I've had to change my game because of the big fella. I'm just waiting my turn. My time will come." When informed of the comments, Abdul-Jabbar attempted to channel Mark Twain by replying, “I'm not dead yet. The reports of my demise have been greatly overrated."

9 9. Derek Jeter and Alex Rodriguez

Jeter and A-Rod were actually friends long before they were ever teammates and they remained friends through 2001, when A-Rod openly criticized Jeter and noted that the Yankees shortstop did not exactly have to carry a heavy burden in New York, saying in Esquire, "Jeter's been blessed with great talent around him. He's never had to lead ... You never say, 'Don't let Derek beat you.' He's never your concern.''

The relationship became fractured after those comments, but the pair were able to put aside their differences when Rodriguez joined the Yankees, perhaps owing to the fact that Rodriguez was willing to move from shortstop to third base in order to accommodate Jeter. After all of the controversies that Rodriguez has brought upon the Yankees in recent years, Jeter is generally unwilling to discuss anything relating to Rodriguez, and when asked about A-Rod recently, Jeter declined to offer an answer, reportedly glaring before saying, “This is not an Alex story.”

8 8. Floyd Mayweather and 50 Cent

OK, so maybe 50 Cent isn’t an athlete, and despite the fact that he is built like one, it is at least plainly clear from his attempt at throwing out the first pitch at Citi Field that professional baseball is never in his future. But he is known for being in a long-standing feud with boxer Floyd Mayweather, beginning with a business venture that Mayweather apparently backed out of while leaving 50 Cent with a 7-figure loss. There have been many comical moments that have come out of this particular feud, but the best has to have been when 50 Cent insinuated that Mayweather was illiterate by challenging him to read a single page of Harry Potter without making a mistake.

7 7. Brent Barry and Tony Parker

Barry and Parker shared a great deal of success while playing together for the San Antonio Spurs, but despite all of the successful championship runs, Barry probably never expected that he would also be sharing his wife with Parker at any point during their friendship. While all of the parties involved deny anything physical ever occurring between Barry’s wife and Parker, Eva Longoria, Parker’s ex-wife, cited Parker’s relationship with Barry’s wife as infidelity and cause for divorce, saying that Parker had sent “hundreds" of inappropriate texts to Barry’s wife.

6 6. Lance Armstrong and Frankie Andreu

Armstrong and Andreu were teammates on the US Postal Service cycling team that dominated the Tour de France for several years, but their friendship was ultimately derailed after the team’s second Tour de France victory in 2000. According to Andreu, the dissolution of their friendship resulted from his refusal to engage in the doping program that Armstrong was at the center of, while Armstrong counters that Andreu was let go over a contract dispute. Andreu and his wife have since given countless interviews about the breadth of Armstrong’s PED use and have seemed to revel in Armstrong’s recent fall from grace. After Armstrong gave his infamous interview in which he disclosed his PED use, Betsy Andreu, Frankie's wife, said, “The guy’s a professional liar. How are we supposed to believe him?”

5 5. John Terry and Wayne Bridge

Terry and Bridge were once close both on and off the pitch, but the close friendship they had developed would soon unravel when Terry became involved with Bridge’s wife. The affair apparently began shortly after Bridge’s transfer from Chelsea to Manchester, and what started with Terry offering his “comfort and support” in the aftermath of the couple's breakup eventually turned physical between the pair, leading to a four-month long relationship that ultimately turned the friendship between Terry and Bridge into nothing short of hatred. The next time Bridge and Terry met on the pitch, Bridge stared Terry down until he looked away before refusing to shake hands before the match.

4 4. Billy Martin and George Steinbrenner

When a manager is let go by an organization, both the manager and team generally accept that it is time to move on. Such was not the case with Billy Martin and the New York Yankees, as Martin was hired – and fired – on five separate occasions as the manager of the Yankees. Owner George Steinbrenner, known for his volatile persona, clashed with Martin over and over again, but there were enough times when the two got along well enough that Steinbrenner always considered bringing Martin back to the Yankees dugout. Steinbrenner and Martin were at the center of what the New York press called the “Bronx Zoo,” and Martin once said of Steinbrenner and outfielder Reggie Jackson that “one's a born liar and the other's convicted."

3 3. Ray Allen and Kevin Garnett

The two NBA superstars joined forces on the 2008 Boston Celtics to help lead the franchise to its first title since the 1980s, with the team being united on all fronts with the help of Doc Rivers’ Ubuntu philosophy. But when Ray Allen left the Celtics in free agency to join an Eastern Conference rival in the Miami Heat, Garnett and Allen’s relationship went into a deep freeze, with Garnett claiming that he had no plans to talk to Allen and that he no longer had his phone number. When the Celtics and Heat met for the first time after Allen’s departure, Garnett would not even look at Allen and refused to shake hands with his former teammate. According to reports, the two haven’t spoken since and have no plans to do so.

2 2. Penny Hardaway and Shaquille O’Neal

Shaq is known for his outsized persona, and it has led to a lot of clashes with teammates over the years. Hardaway was O’Neal’s first running mate in Orlando, and the two looked like they could have been a dominant pair had they been able to stay together longer. While the pairing started off reasonably well, teammate Horace Grant recently noted that egos began to get in the way and Shaq ultimately left to join the Los Angeles Lakers via free agency.

While time has softened the hate between the two and Shaq often speaks fondly of Penny while on the air with TNT, Hardaway said at the time that he was “blindsided” by the news, as he found out that Shaq was leaving Orlando during a press conference for Team USA at the 1996 Olympics in Atlanta. Shaq would later insinuate that he carried Penny to the 1995 NBA Finals, just as he carried Kobe Bryant to NBA Championships with the Lakers. Speaking of Kobe…

1 1. Kobe Bryant and Shaquille O’Neal

Shaq and Kobe should have been a match made in Heaven, as a dominant big man paired with an outstanding perimeter scorer are the ideal components to build a championship team around. The Lakers won often, making four trips to the NBA Finals and winning three times in consecutive years. While the pair sparred with relative frequency early on in their time with the Lakers, Kobe still considered Shaq a friend and was disappointed that Shaq didn’t reach out when he faced legal troubles.

The feud lasted for quite some time after that, with both using the media to trade barbs at the other before Shaq was ultimately traded to the Miami Heat. Shaq also famously rapped about Kobe in an astonishingly graphic manner, and Kobe has since referred to Shaq as “lazy,” and, recalling his thoughts about the situation at the time, Kobe said, "I was like, 'F--k him. I'm out here busting my ass. I'm killing myself. And it became insulting. Because I chose to extend my deal with the Lakers to play with Shaquille O' Neal and win championships. I knew what I could have done individually. I could have gone to another team and averaged 35 points a game."