There were so many reasons to lose faith; so many critical moments where your gut told you this just wasn't the Celtics' night. But when push comes to shove, champions emerge, and that's exactly what the Boston Celtics did Tuesday night.

Overcoming numerous obstacles, including an 11-point deficit in the fourth quarter, the Boston Celtics showed the will, heart and determination that was their trademark during a championship run one season ago.

When there is a will, there is a way, and that was the case tonight when the Celtics grabbed a commanding 3-2 series lead in dramatic fashion, winning 106-104 in overtime over the Chicago Bulls.

Paul Pierce

Paul Pierce hit four huge shots that looked exactly like this to push the Celtics to a 3-2 series lead Tuesday night.Elsa/NBAE/Getty

Just 18 seconds after he cut the Bulls lead to three at 83-90, Ray Allen fouled out of the game with 5:27 remaining in regulation on a phantom double-foul call with Brad Miller.

The Celtics offense was continually sputtering in the second half, falling behind 77-66 with 9:28 left in regulation.

The bench provided only five points in the entire game.

They allowed Chicago to grab 14 offensive rebounds and make 11 more free throws than they did.

In the end, none of that matters.

What matters is that Paul Pierce and Rajon Rondo put the team on their backs and defied any notion that the defending champs would fall into a 3-2 series hole. They combined for 14 points over the final 6:55 of regulation, including Pierce's game-tying jumper over John Salmons (which was assisted by Rondo) with 10.5 seconds remaining.

Rondo again pushed for triple-double numbers and finished with 28 points, 11 assists and eight rebounds. His ability to drive to the basket helped the duo of Pierce and himself be unstoppable in overtime.

The two delivered 10 more combined points in an OT that featured identical, back-to-back-to-back, step-back jumpers by Pierce over Salmons from just outside the right elbow.

Their heroics injected life into a TD Banknorth Garden crowd that had seemingly lost all hope in the third and fourth quarters. As the final 2:00 of regulation and 5:00 of overtime ticked off the clock, this building was loud as it's been all season long.

Prior to Boston's run, the Bulls had dictated the tempo of the game over the first three minutes of the fourth. Chicago scored the first seven points of the quarter to open up the game's largest lead at 11. At that point, it seemed like the Celtics were out of legs and the Bulls would run away with the game.

But a quick three-point play by Pierce cut the lead to eight and gave Boston their first momentum since Rondo's buzzer-beating jumper heading into halftime. Their defense began to perform up to expectations and everything continued to click from there.

"When we play our defense and just relax, we're okay," Rivers said. "And I thought we did that."

The Celtics played from behind for the entire fourth quarter and fought tooth and nail to send the game to an extra session. In fact, prior to going up 94-93 with 4:46 remaining in OT, Boston hadn't seen a lead since the 1:30 mark of the third quarter.

After Gordon gave the Bulls a two-point lead off a tough jump shot with 16.6 seconds on the clock, the Celtics turned to Pierce for another clutch shot with Allen on the bench. He wasted no time and took the ball at the top of the key, made a quick jab step and tossed up a fade-away jumper that caught nothing but net. Gordon's attempt at a rebuttal missed and it was on to yet another overtime. This is the first series in NBA Playoffs history featuring three overtime games.

Kendrick Perkins, whose fantastic performance was overshadowed by that of Pierce and Rondo, scored the first three points of overtime for the Celtics to give them a 96-95 lead. Perkins was undoubtedly the unsung hero of this game and set career playoff highs of 19 rebounds and seven blocks to go with his 16 points.

After Perkins' three points, Rondo then scored four of his own to put the C's up 100-97. Gordon and Derrick Rose then responded with four consecutive points to put the Bulls back up by one, at 101-100, with 1:36 remaining.

Rivers opted not to call timeout and the Celtics ran their offense through Pierce. He isolated on Salmons at the top of the key and drained a mirror image of his game-tying shot at the end of regulation to put Boston back up by one. After Gordon came up empty on a three-pointer, Pierce went back to his patented move and once again gave Boston the lead, 104-101.

Bulls coach Vinny Del Negro called a timeout and had to make a decision: go for a quick two, or try to tie the game? His players made their way back onto the court, and on the ensuing inbounds pass Gordon opted for the tie and took a challenged three-pointer in front of the Celtics' bench. Unfortunately for the Celtics, Tony Allen challenged the shot a bit too much and leaned into Gordon's body during the attempt.

In Sunday's Game 4 loss to the Bulls, the Celtics should have fouled to save their lead. This time, with 36.5 seconds left on the clock, fouling was the last thing Boston wanted to do, especially on a three-pointer.

That plan didn't hold true, and Gordon drilled all three free throws to knot the game at 104-104.

It was then Rivers' turn to call a timeout and draw up a possible game-winning play. There wasn't much drawing to be done, though. The message was simple: Give the ball to Paul Pierce.

Pierce took the ball near half court, dribbled the clock down below eight seconds and began his attack. Salmons probably knew it was coming, but there was nothing he could do about it. For the fourth consecutive time in just over five minutes of play, Pierce jabbed with his left foot, stepped back and hit another huge shot from just outside the right elbow that put the taste of a 3-2 series lead in Boston fans' mouths.

"I just thought I didn't over-penetrate tonight," Pierce said. "I took my own time, I got some space off the dribble, and you know, got into my sweet spot and took the shots."

His shot gave Boston a 106-104 advantage with 3.4 seconds left, but with the way this series has gone, it seemed as if everyone knew there was more drama coming.

Out of a Chicago timeout, the Celtics double-teamed Gordon and mistakenly left Brad Miller wide open at the top of the key. He grabbed the inbounds pass and had a wide open track to the basket. But Rondo, who has made so many veteran plays already in this series, added another one to the list. Rondo closed in from Miller's right side and made sure he didn't get an easy score to tie the game.

"We executed the play very well," Vinny Del Negro said. "He was wide open, just couldn't convert."

In making a play for the ball and preventing Miller from finishing, Rondo actually caught him in the face with his arm and caused a stoppage of play due to blood coming from Miller's mouth. It was unclear for nearly two minutes if Miller would be able to stay in the game and take the two free throws, but he finally emerged from a group of Chicago's trainers and coaches and made it onto the court.

Basketball fans will always remember the infamous golf ball-like bump on the top of Scottie Pippen's head during the 1996-97 playoffs. The sight of Miller's mouth may go down just as vividly in NBA fans' minds.

He stepped to the line for the two biggest free throws of his career looking like he just finished a 12-round bout with Mike Tyson in his prime. The right side of his mouth was swollen, bruising and slightly bleeding as he wavered in the air amid dizziness.

The way this series has gone, with so many "Did he really just do that?" type moments, it was certainly possible that Miller would drain both free throws and send the game to overtime.

But the concussion-like symptoms and blown up lips were too large to overcome, and Miller bricked the first free throw. He was then forced to intentionally miss the second, and in doing so committed a violation by not hitting the rim.

Pierce added a free throw with 1.3 seconds left to up the Celtics lead to three and his nightly total to 26 to wrap up the big win.

It was his baskets that gave the Celtics the lead, but it was Rondo's foul that preserved that cushion.

"You always talk about playoff basketball. No layups," Rivers said. "Rondo did it on the very last play and it won the game for us."