For the second straight year, the Miami Heat are the prohibitive favorites to win the NBA Championship.

According to the online sportsbook Bovada, the Heat are 6/5 favorites to win it all. Miami may not have the best record of any team remaining in the playoffs, but they have two of the best players in the game.

For all the negative talk about LeBron James in the playoffs, he's still the number one player in the NBA. He's on the verge of winning his third MVP in four years, and plays alongside the top shooting guard in Dwyane Wade.

The Heat made quick work of the Knicks in the first round, and are on the fast track to the NBA Finals with the Bulls out of the picture. Miami has its flaws, and showed that it can be beaten when they lost in six games to the Mavericks a season ago, but they are the most likely candidate to win the title.

There aren't many teams with a chance of beating the Heat, but there are a few clubs that have a shot to take down the Big 3.

Here are the three teams that can prevent the Miami Heat from winning this year's NBA Finals.

Boston Celtics

The Celtics are the only team in the Eastern Conference that has a chance of beating the Heat.

After looking like a team that's window had passed in the first half of the season, Boston played extremely well heading into the playoffs.

Boston is the only team left in the playoffs that can match Miami defensively. The Heat are known as an offensive juggernaut because of the Big 3, but the real strength of the team is its defense.

Even if Boston can't score against Miami, the Celtics can hold down the Heat as well. Once they get in transition, the Heat are almost unstoppable. It won't be easy for the Celtics to slow down the Heat, but if they can play a half-court game with Miami, they'll have a chance to win.

The Heat would have the best two players on the court in a potential, but the Celtics might have the next best three. Rajon Rondo and Paul Pierce are two of the best players in the league, and Kevin Garnett had a resurgence in 2012. If Boston gets a few breaks, they have a chance of making it to the NBA Finals

Oklahoma City Thunder

The Thunder were many people's choice to meet the Heat in the finals before the season started.

Oklahoma City could give Miami some real good competition. The teams split their two games in the regular season, and the Thunder won just one more game than the Heat.

OKC is the only team that would have the second best player on the floor in a game against Miami. Kevin Durant is LeBron James' primary competition for the league MVP. If James is the best player in the NBA, Durant is probably second, winning his third straight scoring title this year.

While the Heat are known for having the Big 3, the Thunder have a Big 3 of their own. The combination of Durant, Russell Westbrook and James Harden actually scored more than James, Dwyane Wade and Chris Bosh. The Oklahoma City trio averaged a combined 68.4 points per game this season. Miami's three best players averaged a total of 67.2 points per game.

Miami may be the most athletic team in the NBA, but Oklahoma City isn't far behind. The Thunder would be ready to play the Heat, and wouldn't surprise many people if they beat them to win the title.

San Antonio Spurs

The Spurs are the hottest team in the NBA. San Antonio has won 14 straight games, including the playoffs, and finished with the best record in the West at 50-16.

The Spurs, usually known as one of the best defensive teams in the league, were one of the most dominant offenses in the league. They averaged 103.7 points per game, putting them second behind the Nuggets.

San Antonio doesn't have anyone nearly as good as James or Wade, but their complimentary players are much better than Miami's. The Spurs may have the most balanced team in the league. During the regular season, the Spurs had 10 players who averaged at least nine points per game.

If James or Wade has a bad game, the Heat can have trouble scoring points. The Spurs don't often have that problem because they have so many options.

The Heat are much more athletic than the Spurs, but San Antonio has the best coach in the NBA. Gregg Popovich won the Coach of the Year award, and has four titles. He gets the most out of his players, even when he doesn't have the most talented team in the league.

They are well coached, but the Spurs also have a star in Tony Parker. He was one of the best point guards this season, and could give Mario Chalmers a lot of trouble.

It's hard to find a weakness on this Spurs team. The Heat may be the favorites to win it all, but the Spurs are right behind them.