The Celtics trailed by as much as 16 in the second quarter and 66-57 at halftime, but outscored the SuperSonics 61-37 in the second half to run away with their fifth win in six games.
The SuperSonics shot 66 percent from the field in the first half, but Boston held them to 31 percent in the second half by forcing nine turnovers.
Jefferson was big part of that effort. He helped hold Seattle's starting frontcourt of Chris Wilcox and Nick Collison to a combined nine second-half points after they torched the Celtics for 20 in first two quarters.
"Everybody in this league can score," said Jefferson, who blocked two shots. "Every team, every guy. So it's not about who is going to go out there and score the most points -- it's about who's going out there and getting the most stops. The more we got stops, the easier it was for us to score."
Rajon Rondo, starting in place of the injured Delonte West, scored 20 points and Gerald Green added 19 for the Celtics. West sat out with a mild concussion he sustained in Wednesday's 111-80 loss to Houston.
Jefferson scored 22 in the second half, and Green added 15 on 6-of-6 shooting as the Celtics shot 68 percent from the field.
"The second half was our worst defensive performance of the year, absolutely," Seattle coach Bob Hill said. "Jefferson just went to work. He made quick decisions and he was aggressive."
The SuperSonics led 63-47 with 2 minutes remaining in the second quarter, but Boston scored 10 straight to pull within six.
Watson hit a 3-pointer with 0.5 seconds remaining in the half to extend Seattle's lead, but the momentum had already switched to Boston's side.
"A lot of times games are won when you can hang on to that lead going into the half," Collison said. "They went in [halftime] down in single digits instead of down 16, and they had a whole different mind-set in the second half."
After Rashard Lewis drained a 3-pointer to give Seattle a 79-67 lead midway through the third, the Celtics ran off 17 straight points to take their first lead since midway through the first.
Green scored seven during that stretch, and Jefferson and Pierce each had four. Following five straight points from Green to make it 79-78, Jefferson's hook shot with 2:15 remaining gave Boston the lead for good.
"Big Al's a monster," Green said. "He's doing everything right. He's doing what he does best, and that's scoring. He's getting rebounds. He's dominating the game."
Watson's 3 late in the quarter ended Boston's run, but the Celtics went on an 8-0 run early in the fourth to turn a 93-90 lead into a blowout.
SuperSonics F Danny Fortson sat out after being suspended two games without pay for conduct detrimental to the team. ... Seattle G Luke Ridnour missed his third game with a herniated disc in his neck. ... G Allan Ray rejoined the Celtics after being recalled from the Austin Toros of the NBA Development League on Thursday. ... The Celtics used their 20th different starting lineup of the season after using 18 last year. ... Boston F Ryan Gomes sat out with an injured left foot.