The Celtics are headed back to Los Angeles one win away from taking their 18th NBA championship, after beating the Lakers, 92-86, Sunday night at TD Garden. Here are five reasons that was made possible. (For a complete recap, click here.)

1. Limiting the Lakers’ top two options: Kobe Bryant might have gotten his points (38), but few were easy. Ray Allen was particularly effective against the LA star, staying on his shooting hand from the get-go, with Bryant going just 1-for-4 in the first quarter and 4-for-12 in the first half. Paul Gasol, who was checked by both Kevin Garnett and Kendrick Perkins, couldn’t take advantage of the Celtics’ early willingness to let him shoot from the outside, going just 1-for-4 for the first half. Gasol did show a renewed aggressiveness in the second half, taking six shots in the third quarter. But at the end of the day, Gasol never established himself as the interior threat witnessed in the series’ first few games, finishing with just 12 points.

2. Paul Pierce: It was clear this was Pierce’s time to take top billing when it came to the Celtics’ offense, coming out of the shoot going 7-for-10 in the first half. He then continued in the third quarter, going 5-for-8 from the floor. With Ray Allen and Co. clearly deferring to Pierce, the Celtics captain never stopped displaying the kind of aggressiveness that he hadn’t offered at any point throughout the finals, finishing with 27 points. This was the Paul Pierce who carried the Celtics to their 2008 NBA championship.

3. The Celtics’ overall defense: As promising as it was that the Celtics had held the Lakers to just 33 percent shooting in the first half, the fact that they led by just six points heading into the intermission was cause for concern, especially considering the Celts had shot 65 percent. But the C’s defense never let up. And to cap it off, nobody on the Celtics was getting into foul trouble, with Allen becoming the first Celtic to pick up three fouls with just under eight minutes left in the game. Another sign of the Celtics’ resolve was their rejuvenation on the glass, with the C’s actually out-rebounding LA, 27-22, through three quarters. The Lakers finished shooting 40 percent from the floor, to the Celtics’ 55 percent.

4. Ability to control the paint: Remember the matchup problems the Celtics were supposed to continue to have on the interior? Many of them magically disappeared in Game 5. Leading the way was Kevin Garnett, who found his Fountain of Youth, going 5-for-6 from the floor through the first three quarters while grabbing nine boards and helping control Andrew Bynum (1 rebound) and Gasol during that time. Credit has to go out to Perkins, as well, with the center not only making both his shots from the floor while keeping the Lakers away from the glass, but also keeping his composure. At one point Perkins walked away from a rift with Gasol, holding his hands in the air while pointing to his head as a reminder that he wasn’t going to be coaxed into his seventh technical foul of the playoffs.

5. The point guards: Perhaps statistically, Game 2 was Rajon Rondo’s best game, but Game 5 offered how far Rondo has come as a point guard. He consistently got the ball in the right hands (usually Pierce), while taking few bad shots (as his 8-for-11 showing from the floor would suggest). But it wasn’t only Rondo (18 points) who helped set the tone for the Celtics at the point, with Nate Robinson continuing to play with confidence, albeit not too much confidence. Robinson went 2-for-4 in his 10 minutes, only turning the ball over twice while coming away with a plus-1.