Updated

Auburn Hills, MI (SportsNetwork.com) - A nearly unstoppable performance from Isaiah Thomas carried the Boston Celtics to a crucial win, a 113-103 triumph over the Detroit Pistons that moved the club a step closer to earning a playoff berth.

Thomas poured in a season-best 34 points in 30 minutes off the bench to almost single-handedly keep the Celtics inside the top eight spots in the Eastern Conference. With the win, Boston moved into a tie with Brooklyn for the No. 7 seed with four games remaining in the regular season, with Miami and Indiana lurking a game back in the race.

"One of those nights," said Thomas. "When I got to the teeth of the defense, like 4-5 times it was like nobody was there."

Jae Crowder added 17 points and Brandon Bass chipped in 16 in the Celtics' fourth victory in five games, which in turn officially eliminated the Pistons from postseason consideration.

Boston prevailed despite a pair of big efforts from two Detroit starters, with Andre Drummond finishing with 22 points and 14 rebounds and Reggie Jackson dishing out 15 assists to go along with 21 points. The Pistons also received 19 points and 10 boards out of Greg Monroe in defeat.

Detroit couldn't stop Thomas, however, or a near-perfect performance by the Celtics from the foul line. Boston made 33 of its 34 free throws, while the Pistons attempted just 10 on the night.

"It was Isaiah Thomas, it was 34-10 in free throws," Pistons head coach Stan Van Gundy remarked. "You get outscored by 27 at the line, it's going to be tough to win, and (we had) 19 turnovers. That's the game to me."

The Celtics never trailed after ripping off an 20-0 run that overlapped the first and second quarters, building a lead as large as 19 points in the fourth.

Thomas put up seven points during the tear, three of which came on a buzzer- beating long jumper that staked Boston to a 30-16 advantage after one period. Two Crowder free throws to open the second capped the spurt, during which the Celtics held Detroit scoreless for five minutes.

The Pistons got back in it by putting forth a 13-2 sequence that trimmed their deficit to 40-36 midway through the second quarter, but Boston withstood a 13- of-17 shooting display from Detroit for the frame to build the margin back up to 55-47 at the half.

Detroit continued to close the gap in the third quarter, pulling within 68-67 when Anthony Tolliver's 3-point play finished off a 14-2 flurry. However, the Celtics dominated the final 3 1/2 minutes of the stanza to push the lead back to double digits.

Marcus Smart buried a triple and Thomas and Crowder followed with back-to-back 3-point plays, igniting a 16-2 push that put Boston up 91-74 entering the fourth quarter. Thomas netted eight points in all during the run and tallied 13 for the third quarter.

Detroit made one last charge in the final minutes, with consecutive buckets from Drummond, a 3-pointer from Tayshaun Prince and Jackson's driving layup part of an 11-2 run that cut the lead to 109-101 with 2:17 left.

The Pistons came up empty on their next four possessions, however, as the Celtics held on down the stretch.

Game Notes

Thomas finished 10-of-11 from the free throw line and Crowder hit all nine of his foul shots ... Boston's final four games begins with a tough home-and- home set with the Central Division-leading Cavaliers in Cleveland on Friday ... Prince, traded by the Celtics to Detroit on Feb. 19, had 15 points on 7-of-8 shooting against his former team ... The Celtics have now won five straight on the road, their longest streak since a six-game run from March 4-April 4, 2008 ... The Pistons had a five-game win streak at the Palace of Auburn Hills snapped.