Boston led by 29 but had to hold on late for its fifth win in six preseason games as the Raptors rallied in the fourth quarter, outscoring the Celtics 39-16.
The Celtics led 101-73 heading into the fourth before the Raptors mounted a comeback against Boston's reserves. Toronto's Sonny Weems made a pair of 3-pointers and Marcus Banks made one of two from the line to cut it to 112-108 with 38 seconds left, but Robinson answered with a pair of free throws to push the lead back to six.
Linas Kleiza and Andrea Bargnani each scored 15 points for the Raptors, who have lost three of four.
Boston starters Kevin Garnett and Jermaine O'Neal both played 15 minutes, with Garnett scoring eight points and O'Neal adding four.
Rondo scored 16 of his points in the third, including a 12 for 15 showing at the free throw line, as Boston outscored Toronto 41-30.
Bargnani continued to struggle with his shooting, going 5 for 16. The top pick in the 2006 draft, Bargnani is 16 for 64 in five preseason games.
Boston forward Glenn Davis, who skipped Wednesday's win at New York with a sore left knee, returned to the lineup but fouled out after scoring five points in 10 minutes.
The Celtics shot 7 for 11 from 3-point range in the first half, including two each from Daniels and Robinson, to lead 60-43 at the intermission.
NOTES: Shaquille O'Neal (hip) did not play for the Celtics, who were also without Paul Pierce. Shaq and Pierce are expected to play against the New York Knicks in Hartford, Conn., on Saturday. ... Boston's Stephane Lasme, from Gabon, did not travel to Toronto because coach Doc Rivers wanted to avoid any visa problems at customs. Delonte West (back spasms) also skipped the trip. ... Former Raptors player Charles Oakley attended the game, as did actor Steve Schirripa.