In just one season, the Oklahoma City Thunder have transformed from an immature club blessed with talent but searching for an identity into a genuine title contender.

The pieces to the puzzle essentially remained the same from a year ago but the youthful Thunder played this season with a swagger, a sense that they belonged in the NBA Finals.

"A lot of guys and a lot of people around the league say we're young and we're not able to make clutch shots, perform under clutch moments, and I think it wills us," said 23-year-old guard Russell Westbrook.

That drive will get tested in the NBA Finals when the Thunder face LeBron James and the Miami Heat, another team with a chip on its shoulder for other reasons.

While Miami's Big Three (All-Stars James, Dwyane Wade and Chris Bosh) will be looking to avenge last season's upset to the Dallas Mavericks in the finals and prove they are more than just a glitzy show, the Oklahoma City franchise has not made it this far since 1996 when the club was still in Seattle.

The Seattle SuperSonics won the championship in 1979, the only time in 41 years playing in the Emerald City that they were the National Basketball Association's (NBA) last team standing.

Team owners fought with lawmakers in Seattle and relocated the club to Oklahoma City for the 2008-09 season.

Despite the move, the club retains a distinct Seattle flavor: Four of the team's key players, leading scorer Kevin Durant, Westbrook, shot-blocking specialist Serge Ibaka, and swingman Nick Collison were drafted by the Sonics.

The leader of the band unquestionably is Durant, the NBA's three-time leading scorer who, despite being 6-foot-9 (2.06m), plays with the smoothness of a point guard.

Oklahoma City's top four players, Durant, his high-scoring backcourt mate Westbrook, James Harden and Ibaka are 23 years old or younger. Do not tell Durant they are not ready yet.

"We never just thought that we were supposed to wait our turn," Durant said after the Thunder defeated San Antonio in six games in the Western Conference finals. "We always wanted to go and take everything.

"Coach (Scott Brooks) always emphasizes that every opportunity we step out on that floor is a great opportunity to get better and grow and fight toward our dreams, and we all knew that.

"We've got a long ways to go still. We've just got to take it a day at a time."

To reach the finals, the Thunder bounced the defending champion Mavericks in four straight and then needed just five games to dispatch Kobe Bryant and the Los Angeles Lakers.

Against the Spurs, Oklahoma City lost the first two games before reeling off four straight wins to give the franchise its first appearance in the finals since the Michael Jordan-led Chicago Bulls beat the SuperSonics in six games 16 years ago.

The Thunder have their drawbacks. They do not share the ball very well, a key reason they ranked last in assists this season.

But they are young, athletic, and when the ball is going in the basket, it does not matter if there was an assist. They are not the same unrefined club that lost to the Mavericks last year in the Western Conference finals.

Spurs coach Gregg Popovich is a believer.

"They went through Dallas, last year's NBA champion, then they went through the Lakers, then they went through us," he said. "Those three teams represent 10 of the last 13 championships."

(Reporting By Steve Ginsburg; Editing by Frank Pingue)