Throw Kevin Garnett, who did his normal lock-down job on Chris Bosh, into the mix and you have the recipe for a nearly unbeatable opponent.

It certainly seems that way with the Celtics now having swept all four this season, but Bosh isn't buying that theory.

"We shot ourselves in the foot tonight," Bosh said after the Raptors blew a 10-point lead in the third quarter, rallied to force overtime but then fell 115-109.

"There were a couple of rotations that we made mistakes on. We gave up a couple of layups and on one we left the hottest guy on the court, Paul Pierce, wide open. Out of everybody, Paul Pierce and Ray Allen seem to get open at the wrong time."

For Bosh the problem last night, as it was Sunday when Allen was going off for a season-high 36, was guys overhelping, which lead directly to the open looks.

"We get so caught up in helping out baseline that we do it too much," Bosh said. "And while helping out a teammate is a great thing and I love it, but if we have our guy contained don't overhelp. We got caught doing that a little bit."

Pierce, showing no signs of any problems after banging knees with Brian Scalabrine in Toronto, knocked down a game-high 39, including 14 in the third quarter when the Celtics clawed their way back into a game they had trailed since midway through the first. In overtime Pierce set the tone, scoring the first five points, one on a wide open three-pointer.

"You see Paul going like he's going you let him take care of the buckets and I'll try to take care of the defence," Garnett said of his approach to last night's game.

The overtime loss was a far better showing by the Raptors than Sunday, but in the end it was just another loss to the Celtics.

Not even Andrea Bargnani's overtime-forcing three-pointer with a second left in regulation is going to make this one any easier to digest.

Bosh, who spent most of the night with Garnett just about inside his uniform with the defence so tight, wound up with 18 points on 6-of-11 shooting. From the third quarter on he was just 2-for-6, including the extra period, when he managed just two free throws.

"You work hard to get open, then he overplays you," Bosh said of Garnett's skin-to-skin defence. "Then he has help behind him so it's tough. I made the right pass but in situations like that I want my team to be aggressive. Guys have to look for their shot."