"Bosh was just too much for us," Pacers coach Jim O'Brien said. "He played like he normally plays. He's a great basketball player."
Toronto has won 15 of 20, pulling within 4 1/2 games of Boston for the Atlantic Division lead. The Celtics lost 90-89 to the Los Angeles Lakers on Sunday, their third straight defeat.
With his team surging and the Celtics struggling, Bosh is hoping the Raptors can win another division title, like they did in 2006-07.
"I've kind of been holding on to that feeling for a while now," Bosh said. "I want to get back to that. I want to get back to that feeling and I think we have an opportunity to do that here.
"I have the confidence, I think the whole team has the confidence," Bosh added. "We have to keep winning and hopefully [Boston] will continue to struggle, or one of those top four teams."
Teammate Jarrett Jack said the Raptors have bought in to Bosh's goal.
"We look at the standings every day," Jack said. "We want to create some separation from the teams behind us and gain some ground on the teams in front of us."
Jack scored 16 points and was one of seven Raptors to reach double figures as Toronto shot a season-best 60.2 percent (50 for 83) and topped 100 points for the 13th straight game.
"We did not defend at a level that would allow us to beat these guys," O'Brien said. "Giving up 60 percent is not going to get it done."
Toronto's Hedo Turkoglu, who had season highs of 26 points and 11 rebounds Thursday at New York, was knocked out in the first minute of this one when he took an elbow in the face from Mike Dunleavy. Turkoglu suffered a fractured orbital bone, beneath his right eye, and will be re-evaluated Monday.
Toronto will also try to find a protective mask for Turkoglu before its next game, Tuesday at Indiana.
Danny Granger came in averaging nearly 30 points in his past three games against Toronto but was ineffective in this one, tasked with guarding Bosh and slowed by early fouls. Granger shot 3 for 13 and scored just eight points.
"He's a tough guard," Granger said. "I mean, he's an All-Star. I've played well against him in the past but, once I got into foul trouble, there's not much I can do."
The Pacers, who overcame a 23-point, second-quarter deficit to beat Toronto 105-101 on Jan. 11 in Indianapolis, trailed 95-86 through three quarters before tying it on Head's 3-pointer with 7:59 left, capping an 11-2 run to start the fourth.
Bosh made three baskets as the Raptors replied with an 8-1 spurt, making it 105-98 with 5:39 remaining, and Toronto wasn't challenged again.
"We just ran out of gas," a downcast Granger said. "We just didn't have it."
Bargnani, hampered by a sore foot and held to just two points in Thursday's 106-104 victory at New York, started for Toronto but rookie DeMar DeRozan (sprained right ankle) missed his third straight game, with Sonny Weems taking his place and scoring a career-high 13 points.
Jose Calderon scored 10 points in the second quarter and Jack added six more as Toronto led 63-59 at the half.
Toronto pulled away in the third behind 12 points from Bosh and seven from Bargnani, taking a 95-86 edge into the fourth.
Toronto has won 11 of 12 at home. ... The Raptors shot 59.2 percent in a 131-124 loss at San Antonio on Nov. 9. ... Bosh had a season-high seven assists. ... Toronto's 50 field goals were a season high. ... Indiana is 6-27 when allowing 100 or more points. ... The Raptors welcomed 400 members of the Canadian military as part of Troops Night celebrations.