In the summer of 2007 when Danny Ainge assembled the Big Three, Rajon Rondo was an unproven point guard given the keys to the car but was largely seen as being along for the ride as the Celtics won their 17th World Championship.

Almost three years later, Rondo's firmly ensconced in the driver's seat with the pedal to the metal as the engine that makes this team go. And if they're going to win it again, Rondo will be the one driving them to the promised land.

Rajon Rondo

The Cavs had no answer for Rajon Rondo in Game 4 at the Garden, as the Celtics point guard posted a ridiculous triple-double and took over the contest.
Nathaniel S. Butler/NBAE/Getty

On Sunday, Rondo dominated Game 4 against the Cleveland Cavaliers at the TD Garden in nearly every available facet from jumpstreet, pressuring the ball, pushing the pace, dealing out 13 assists, chasing down 18 rebounds and scoring 29 points seemingly at will. The 97-87 victory tied the series at 2-2, and the C's will head to Cleveland for Tuesday's Game 5 looking to steal another game on the road against the Cavaliers.

Over the past season, there's been a transition underway as Kevin Garnett battled injuries, Ray Allen faced trade rumors, and Paul Pierce began subjugating his game and picking his spots. Rondo's emerged as one of the league's top point guards, and the Celtics are now his team.

"I wouldn't be here if they didn't want me leading this team. From Day One when they made that big trade, I think seven or eight players were traded that summer. Like I said, I'm here obviously for a reason; those guys trusted me, the staff trusted me and the organization did. So I'm very confident in what I do," said Rondo at the postgame podium, about the only place in the building where he didn't look comfortable on Sunday.

He's never appeared to enjoy doing interviews and has been known to skip out on the press after big games, but there was no avoiding the attention after dismantling a Cavaliers team that has yet to find a way to stop him. Nearly every question in the postgame press conference revolved around him, and as he becomes the face of the franchise over the next few seasons, he'll eventually have to acquiesce to regular requests for media access.

But that's about the only under-developed area of his work -- heck, he's even shooting jumpers quite confidently these days. And after four years manning the point, Rondo's essentially become an extension of Head Coach Doc Rivers on the floor. When at his best, Rondo quarterbacks (he was a QB in high school) his team with near telepathy when it comes to executing his coach's game plan.

"Doc and I...we're always on the same page, that's how I feel. As far as being a leader I just have to continue maturing, each year I'm going to continue to get better. This is my fourth year with the team, (my) third leading the team," Rondo said. "The starting five has been together for three years now, and we just have a better feel for each other."

Rondo had more than a feel for Game 4. He had absolute command of Game 4, and his triple-double performance was one for the ages. When history looks back on the "Rajon Rondo Game" as it will inevitably be called, it will likely mark the passing of the torch from the Big Three Era to the Rondo Era.

"I mean, he's a point guard now that runs our team and has complete control of our team. When we won it, he was still learning how to be a point guard. He was still trying to figure out how to help a team just win," Rivers said, contrasting his point guard from the 2008 championship squad to the one who runs his team today. "Now we rely on him to win."

His Sunday stat line is worth repeating: 29 points, 18 rebounds, and 13 assists. According to an e-mail from NBA spokesman Tim Frank, Rondo's afternoon puts him in the company of NBA legends Oscar Robertson and Wilt Chamberlain, who are the only players in NBA Playoffs history to accumulate more impressive triple-doubles.

Celtics P.R. chief Jeff Twiss, a team employee since the late 70s, said he's seen great games from Tiny Archibald and the late Dennis Johnson, but couldn't remember a Celtics point guard completely dominating a contest the way Rondo did. "That was Bird-like today," Twiss said in his office later that evening, with the game ball from Game 4 in tow, due to be delivered to Rondo at Monday's film session.

Rivers, a former point guard himself, often says that the team with the best player in a series usually wins the series. Before Game 3, he was asked if Rondo was emerging as the best player in the series, and at the time the coach retorted, "there's a long way to go." Four games in, Rondo's continuing to make a case for that title.

On Sunday, Rondo was the best player on the court by any measure, so much so that the Garden crowd gave him an "M-V-P" chant late in the fourth as LeBron James, officially named league MVP before Game 2, stood by and watched. On this day, Rajon Rondo was the best player in the building, the best player in the league, and presumably the known universe.

Even the Chosen One himself had to recognize.

"He's kind of their engine who really gets them going as far as running down the court and making plays. He does everything for them and you can see it tonight," James said of Rondo. "His performance was unbelievable. For him to have 18 rebounds for a point guard was great. 13 assists means he's getting everyone involved and he's getting himself involved. It's always a team effort because it's a team game but Rondo was definitely the difference maker."

The Cavaliers are still trying to find a way to stop Rondo, who's utterly dominated them in the two Celtics wins, and most of Game 1 as well. Mo Williams can't handle him, Anthony Parker is too slow to stay with him, and James seemed on board with the suggestion that he may have to guard him going forward.

Even so, Rondo did a lot of his damage when he wasn't being guarded at all, on the defensive end. Rivers made a point of recognizing the pressure he put on Cleveland's point guard as he pressured the ball full court, and Rondo grabbed 14 of his 18 rebounds on the defensive end, sneaking in from the perimeter to dislodge rebounds from the Cavs big men or corralling long caroms from off-target perimeter jumpers. James pointed out that the 6-foot-1 Rondo (calling him a "unique and rare talent in this league") plays more like a 6-foot-9 guy given his long arms and quickness that allow him to beat bigger opponents to loose balls.

And when Rondo rebounds, he loves to start the fast break. He was looking to push the pace on nearly every possession Sunday, and the Celtics played their best transition game in recent memory as a result.

"Yeah the game got tight, but a lot of teams would probably slow it down and get good shots. I turned the ball over a couple of times but other than that I was trying to just keep attacking," Rondo said of his aggressive mentality. "[Glen Davis] had a couple of leak outs, Tony (Allen) as well. Tony and I were on a break together a couple of times so I just wanted to continue to attack because that's how we got the lead at first, and I just tried to continue to do the same thing."

That approach is the mark of a maturing veteran playmaker, and he's come a long way since being one of the "Other Two" to play alongside the Big Three. For Kevin Garnett, a man who casts one of the larger shadows in the league, it's gratifying to see Rondo emerging as a star in his own right.

"Well, the difference is that we really didn't have any expectations...I really don't think that he was really on the radar, and I think that it bothered him a little bit. He is a very powerful person, a very competitive player," Garnett said, comparing his point guard to the relatively unknown 2008 model, and noting that Rondo's offseason work lead to his breakout season in 2009-10. "It is just good to see it pay off. It's the reason you work your butt off in the summer time to have games like this."