Thomas had 29 points and a career-high 15 assists for Boston, which made 17 3-pointers for the second straight game while defeating the Utah Jazz 115-104 on Tuesday night.
Thomas was coming of a 52-point night Friday against Miami, but it was his passing that helped the Celtics overpower the Jazz, who entered holding opponents to an NBA-low 94.5 points per game.
"I didn't plan on it but I just take what the defense gives me," said Thomas, whose previous high for assists was 13. "When I attacked, they showed more than one guy and my job was to just get the ball to the open guy."
Thomas did just that, 15 times while turning the ball over only once. Al Horford and Jae Crowder added 21 points apiece and Avery Bradley scored 14 for the Celtics, who have won four of five and eight of 10.
Boston coach Brad Stevens gave his players a couple of days off following Friday's win over the Heat and said it showed Tuesday.
"We looked fresh. We haven't looked fresh in a while," Stevens said. "We need to take these days off as seriously as we take practice days and make sure we're getting rest and staying off our feet. Hopefully that has a cumulative effect as we move into some of the more intense parts of the schedule."
Al Horford and Jae Crowder added 21 points apiece and Avery Bradley scored 14 for the Celtics, who have won four of five and eight of 10.
The Celtics ended Utah's four-game winning streak and beat the Jazz for the ninth straight time in Boston.
Utah defeated the Nets 101-89 on Monday night before hopping a short flight to Boston. The Jazz were without second-leading scorer George Hill, who was out with concussion-like symptoms, and could not overcome a 17-point deficit the Celtics built in the second half.
"They did a great job moving the ball," Utah coach Quin Snyder said. "They got jumps on the possession and it's tough to catch up because of their quickness. It's a very quick team."
Joe Johnson finished with 17 points for the Jazz, who managed to chip away at the lead before fading down the stretch.
"I think from the beginning there were a lot of defensive breakdowns," Hayward said. "We gave up way too much in transition, so they got rolling and saw the ball go through the basket. It made it a long night for us."
Thomas' 3-pointer with 2:53 left in the second quarter started a 10-4 run that gave the Celtics a 54-45 halftime lead. Boston stretched it to 68-54 early in the third and Crowder hit his fifth 3-pointer to make it 83-66.
Boston was up by 15 early in the fourth before the Jazz used an 11-3 run to pull to 98-91 on consecutive layups by Johnson. That was as close as it got and the Jazz were forced to foul late, sending Thomas to the line four times. He was perfect from the stripe for the second straight game.
BIG IN BOSTON
At 5-foot-9, Thomas doesn't appear to be much of a threat to drive inside -- until teams try to stop him. He made five 3-pointers against the Jazz, half of his 10 field goals, and has scored at least 20 points in 19 straight games. He also caught the Jazz off guard several times by driving to the hoop, then kicking the ball back outside to a teammate open for a 3.
"He did it in all kinds of ways," Snyder said. "The best plays he made and the most impactful were when he got to the rim and he'd go up and find people. He was finding people everywhere."
Jazz: Raul Neto banked in a 3-pointer at the buzzer to give Utah a 29-28 lead entering the second quarter. ... Hayward and Shelvin Mack were teammates at Butler under Stevens. The 2009-10 Bulldogs clinched a Final Four berth in Salt Lake City with a win over Kansas State on March 27, 2010. ... Boris Diaw scored 15 for Utah, and Favors had a career-best seven assists.
Celtics: Boston again tied its season high for 3s. Crowder and Thomas each hit five from beyond the arc. ... Bradley returned to the lineup after missing one game with an illness. ... The Celtics have not lost at home to the Jazz since March 14, 2008, when Utah won 110-92.
Jazz: Visit Toronto on Thursday in the third of a five-game road trip.
Celtics: Host Philadelphia on Friday night. The Celtics have won eight straight over the 76ers.
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