Kevin Durant vs. LeBron James: Who's the Best Player in the NBA?

He led the Thunder past the Spurs on Wednesday night in Game 6 of the Western Conference Finals, as Oklahoma City advanced to the NBA Finals.

The OKC star had an incredible series, averaging 30 points, seven rebounds, and 5.6 assists per game on 55.6 percent shooting. With the way Durant has played this season, it's hard to think a better player in the entire league.

For the past several years, LeBron James has been considered by many to be the best player in the NBA.

He's won three of the last four MVP awards, and has averaged over 26 points, six rebounds and six assists every year since the 2004-2005 NBA Season.

James has also been a winner throughout his career. He hasn't always gotten the job done in the playoffs, but his teams have been immensely successful in the regular season. The Cavalier and Heat teams that he's been on have averaged more than 55 wins per year over the past seven seasons.

The small forward has gotten the job done with minimal talent around him, and showed his worth when Cleveland won 42 fewer games in the season after he left for Miami.

All of his credentials make it hard to argue that LeBron James is not the best player in the league.

However, Kevin Durant's recent success has at least raised the question of whether or not James is the NBA's top star.

Durant came into the league three years after James, but he has been almost as good as anybody over the past few seasons.

The Oklahoma City forward is the best scorer in the NBA. He's led the league in scoring for three straight seasons, winning the title this year, while averaging 28 points per game.

Durant didn't come into the league as well-rounded as LeBron, but he's getting closer to him every day. He averaged career highs in 2011-2012 with 7.5 rebounds and 3.3 assists per contest.

He may not be as dominant as James on the defensive end, who's been named to the All-Defensive team four times, but Durant's defense keeps improving. He sometimes guards the opponent's best player at the end of games, and can hold his own as a two-way player.

As far as winning goes, Durant has had even faster success than what LeBron enjoyed. In the past three years, the Thunder have averaged over 54 wins in an 82-game schedule. James' teams didn't win that many games until his sixth season.

The biggest argument that can be made for choosing Durant over James as the best in the NBA is their play in the postseason. 

It's somewhat difficult to compare what they've done in the playoffs because James is older, but Durant has already played 38 career postseason games.

Both players' stats in the playoffs are comparable to their regular season numbers. They each average more points and rebounds.

But stats don't tell the whole story.

James has developed a reputation for coming up short in big moments. He's certainly had games in the playoffs where he's been unstoppable, but there are times, in the fourth quarter, when he doesn't play nearly as well as he should.

He's had a few infamous subpar performances, such as Game 5 against Boston in 2010 or Game 4 against Dallas in 2011, where he may as well not have shown up.

The same can't be said for Durant. He's hit game-winning shots, and made clutch free throws down the stretch to ice multiple games for the Thunder.

Durant is set to play in his first NBA Finals, so he's yet to face scrutiny on the biggest stage. But it's hard to imagine him performing worse than James has in his 10 games. James has a career average of 19.5 points, 7.1 rebounds and 6.8 assists on 41.7 percent shooting from the field in the finals.  

Four of those games came when James was with the Cavs in 2007 and he didn't have much help around him. Nevertheless, that's a precipitous drop-off from his regular numbers.

Few people will argue that James is not more talented, but his lack of rings has raised the question of whether or not he'll ever reach his full potential.

Part of Durant's success can be attributed to his supporting cast. Russell Westbrook and James Harden are two of the best young players in the game. Serge Ibaka came in second for this year's defensive player of the year award.

James never had close to that amount of talent when he was in Cleveland. He has Dwyane Wade and Chris Bosh with him in Miami, but his other teammates aren't very good.

Durant will finally get his chance to prove that he can be successful in the championship round when the Thunder play the winner of the Heat-Celtics series.

If Miami is able to defeat Boston, James and Durant will face off for the NBA title. Perhaps, then we will truly find out who is the best player in the NBA.