BOSTON -- If Rajon Rondo's career path were a No. 2 pencil, it'd currently be sketching a lightning bolt on its accompanying canvas.

Let's start from the bottom of that bolt, where Rondo played the role of a relative unknown, a castoff in the distant shadows behind three legendary players during the 2008 NBA Finals.

Rajon Rondo

Rajon Rondo was just glad to be along for the ride during Boston's run to the 2008 NBA Championship.
Kevin C. Cox/NBAE/Getty Images

Rondo navigated through that maze of a playoff run as a wide-eyed, second-year ball handler whose job was simply not to lose a game for the resurgent Celtics. He wasn't asked to win games -- his legendary peers would take care of that.

"You know, Rondo, we believed in him as a starting point guard, but it was hard to fully trust him," said Paul Pierce, referencing the young and inexperienced version of Rondo in 2008.

Despite that wavering trust, Boston still managed to win its first championship banner in 22 years, but it did so with the young point guard taking in one of the most historic comebacks in NBA history. He took it in the same way Jack Nicholson did -- from a front row seat in the Staples Center.

"The 24 (point deficit), whatever the number comeback was that we had against the Lakers (in 2008), Rondo wasn't on the floor the entire time," was what Doc Rivers recalled of the epic Game 4 comeback during the '08 Finals. "We took him out in the middle of the third and he never played again in that game."

Why would the starting point guard now play in the most important quarters of the series, you might ask? Well, for starters, Rivers had found a lineup that clicked and it turned the game around in an instant. Rondo wasn't a part of it. Second, Rondo was still an immature point guard at the time and Rivers didn't know how he would respond in that situation.

Oh, how things have changed.

Said Rivers, "That would never happen now."

It certainly wouldn't, because in just two years' time, Rondo has transformed from the brother in the back seat who's just along for the ride to the man who carries the keys to the car. He is now a household name, an All-Star, who has driven those same three legends to the 2010 NBA Finals.

Meet the top of that lightning bolt.

Rondo has been absolutely dominant in his third postseason, embarrassing former All-Star point guards and knifing up defenses like a butcher does steaks. Entering Game 1 of the Finals, Rondo is averaging nearly 17 PPG to go along with 5.3 RPG and 10.0 APG. He also recorded historic numbers -- we're talking on par with only Oscar Robertson and Wilt Chamberlain -- with his 29 points, 18 rebounds and 13 assists during Game 4 of the Conference Semifinals against Cleveland.

Not bad for a player just two years removed from riding the bench in the most important quarter of the season.

So how did this point guard skyrocket from the bottom of that lightning bolt to the top? Well, it's easy -- he grew up.

"Two years ago he was still trying to find his own way," said Rivers. "As a player he probably wasn't sure who he was going to be as a player yet, and I think now he has a much better (idea) obviously."

Kevin Garnett, Rajon Rondo

Kevin Garnett and the rest of the Celtics have embraced Rondo's development and now trust him to run the show.
Kevin C. Cox/NBAE/Getty Images

Rondo seemingly found himself during the 2009 postseason, when he was heavily relied upon as an offensive force while Kevin Garnett, the team's emotional leader, watched from the sideline with an injured knee. Rondo's numbers last postseason were actually better than in this postseason, as he nearly averaged a tripe-double through 14 games with 16.9 PPG, 9.7 RPG and 9.8 APG. He outdueled Rookie of the Year point guard Derrick Rose in a First Round series for the ages and nearly led the C's past the eventual Eastern Conference Champion Orlando Magic in the next round.

That's when everyone jumped on the Rondo Train and the hype has been building ever since. Reporters ran ramped by tabbing him as the next player to average a triple-double for a season, a youngster who was ready to take over the Celtics, a floor general who was ready to out-perform every point guard in the league.

But what he still wasn't ready for was to be a leader, and that resulted in his name swirling around the rumor mill throughout the summer of 2009. This is the jagged, downward dip in Rondo's lightning bolt.

While Danny Ainge and Rivers continually denied that they were not trying to trade their point guard, they did acknowledge the fact that he needed to grow up.

"There were just a couple situations where he was late this year, I don't know if he was sitting in his car, but showed up late and the rest of the team was there," Ainge told WEEI that summer. "We have team rules and you have to be on time. He was fined for being late, he said he was stuck in traffic, and it's just unacceptable.

"He's got to grow up in some cases."

And so Rondo went to work. He spent the summer working on his game with former NBA sharpshooter Mark Price, who is renowned as a top shooting coach. The hope was to improve Rondo's shot to the point where defenses had to pay attention to him, rather than leaving him to double-team his fellow stars. Consider that time well spent.

As Rondo explains, his improved shot has led to improved confidence.

"I think with success comes confidence, so right now I'm doing pretty good on the court," he said. "I'm pretty successful being such a young point guard. Luckily it's my second Finals already, so I'm pretty confident in my game, and my coaching staff has given me confidence and my team gets around me, so I'm trying to become a better player each year, each game."

A former point guard himself, Rivers has watched the evolution of Rondo right in front of his eyes. He has seen Rondo's confidence improve along with that jumper, resulting in any leadership and maturity questions being thrown out the window.

"As far as two years ago, he's just more mature," said Rivers, comparing the old Rondo to the new. "He's a better basketball player than he was two years ago. Our players trust him now."

With the trust now in tow, Rondo can now do the entertaining for Nicholson instead of being entertained with him. He's got a chance to lead the Celtics to glory, and if he does, who knows where that lightning bolt will stop.