BOSTON — If Boston is supposed to be losing games in the interest of winning Ping-Pong balls, no one told Paul Pierce.

The captain made an 18-footer to force overtime, then drained a 3-point shot to force double overtime in last night’s 105-96 win over the Orlando Magic.

Pierce, who had a quiet 18 points through the first 47 minutes of the game, caught fire with the game on the line, hitting the 18-foot jumper to force overtime and then scoring all seven of Boston’s points in the first extra period — the first two on a tough fadeaway, the third and fourth on another difficult jumper, this one off his right foot, and the final three on a less-than-pretty trey.

Pierce created just enough separation from Grant Hill, who a minute earlier had played some great defense in denying him the ball on the wing, and threw up his shot, which swished through with about 20 seconds left in the first overtime and brought the TD Banknorth Garden crowd to its feet.

He finished with 32 points — 19 after halftime — and grabbed seven rebounds and added five assists, against one turnover. The effort was all the more impressive because Pierce’s bursitic and surgically repaired left elbow was once again bothering him and coach Doc Rivers had considered taking him out of the game because he was in pain.

As the first overtime belonged to Pierce, the second one was all about Al Jefferson.

Challenged by Rivers to be more aggressive, the young big man scored eight points, including a nifty 10-foot hook shot that put Boston up, 97-94, a lead that grew further when pesky rookie Rajon Rondo tipped the ball away from a Magic player and Delonte West chased it down and fed the ball to Jefferson for the dunk.

Jefferson recorded yet another double-double, with 23 points and 13 rebounds.

Kendrick Perkins, who was able to stay out of foul trouble, also had a double-double, with 11 points and 12 rebounds.

It was the second straight game the Celtics have played a potential playoff team tough, having beaten Atlantic Division leader Toronto on Monday night. Orlando came into the game in seventh place in the Eastern Conference but was just a half-game ahead of New Jersey and a game and a half ahead of Indiana.

The Celtics took the lead early in the game and, despite some foul trouble, held the advantage until 7:35 remained in the fourth quarter. At halftime, three players — Jefferson, Gerald Green and Leon Powe — each had three fouls, which was distressing because Boston is down to just 10 healthy players.

One of the keys to the game was the way in which Boston was able to limit Magic star Dwight Howard offensively. A defensive beast with 14 boards and six blocks, Howard had just 12 points, on 4-for-9 shooting, and he didn’t help his team’s cause by making just 4 of 12 free throws overall.

Rivers credited Perkins with shutting down Howard.

“When Perk was off the floor, Dwight Howard was Dwight Howard. When Perk was on the floor, he guarded him (well). He was the only one for us who could do it,” the coach said.

Perkins also played well against the Raptors’ Chris Bosh on Monday, and said it is one of his goals to become one of the best defensive centers in the league.

Rivers said Boston won by executing throughout, and last night it was able to “mentally (stay) in the game.”

“The thing I love is our guys stayed loose throughout the game,” Rivers said.

“They executed down the stretch. It was a great win for us. A team with nothing to play for just keeps playing to ruin everybody else’s season, too. That’s pretty neat.”

Before last night’s game, Rivers said the thing that impresses him the most about the Magic is the number of 24-second violations they have caused on the defensive end. They lead the NBA by a large margin in that category. Those words must have been ringing in his ears later, when Boston twice couldn’t get a shot off in 24 seconds in the closing minutes of regulation, turning the ball over both times. The first came with the teams tied, 77-77, and the second one in the final minute, when the Celts were trailing, 83-81.

smanza@projo.com