BOSTON — While the Celtics fought against the Thunder, they couldn’t close the gap by the end of the night. The C’s lost 118-112 to the Thunder on Wednesday at TD Garden, snapping their five-game win streak. The C’s dropped to 47-19 on the season while the Thunder improved their West-best mark to 54-12.

The Celtics fired early and often from 3-point land, and in the process, they set a new NBA record. While the Thunder racked up points in the paint, the C’s instead bombed away from deep to start the night. The C’s shot 36 3-pointers in the first half alone, the most in any half in NBA history.

While the teams were stylistically different, it was a close game throughout the night. The Thunder built a 12-point lead midway through the third quarter, but the Celtics closed it to a tie game heading into the final frame. The C’s ran out of the gas down the stretch, though, as the Thunder rode their relentless defense to the win.

Both teams were each without a key starter. The Celtics missed Kristaps Porzingis for the seventh straight game due to an illness. The Thunder didn’t have Jalen Williams, who’s dealing with a hip issue.

Jayson Tatum was huge with 33 points, eight rebounds and eight assists. Al Horford added another 18 points, 10 rebounds and six assists; Derrick White had 22 points and eight rebounds. Shai Gilgeous-Alexander, the MVP candidate, finished with 34 points and seven assists for the Thunder. Chet Holmgren was also important with 23 points and 15 rebounds.

The Celtics wrap up their seven-game homestand as they next face the Heat at 7 p.m. Saturday in Miami. Here are four takeaways from Boston’s loss to Oklahoma City:

Not enough: While Tatum took over parts of the game, the Celtics couldn’t muster up enough production against this stout defense. Their 3-point shooting went cold in the second half while the Thunder absorbed each of the Celtics’ blows on the night. Brown had a forgettable game as he fouled out with 3:36 left in the game. He was just 5-for-15 from the field for 10 points. While Horford and White also had big nights to pair with Tatum, plus a side of Luke Kornet (nine points, four rebounds), the C’s didn’t get enough from the rest of their roster.

Big-game factor: With the Celtics having so many marquee opponents recently, they’ve unleashed their might in those games. That was again the case Wednesday as their guys played heavy minutes. Tatum finished with 41 minutes on the night while Brown played 38 before fouling out. Horford didn’t play as much as he did in the Lakers win, but the big man also played 34 minutes Wednesday. These games are great practice for the playoffs where rotations are tight as the C’s lean on their best guys. Plus, they were again without Porzingis.

Shooting away: Not only did the Celtics set a new NBA record for attempted 3s, they didn’t even make a bucket inside the arc in the first quarter. Of their 24 field-goal attempts, 22 of them were 3-pointers in the opening frame. The Celtics finished 20-for-63 (31.7%) on 3s for the night. In the second half, the 3s dried up as the C’s shot 5-for-27 from deep. On the flip side, the Thunder got to the free throw line consistently. They were 25-for-35 on free throws while the Celtics were 10-for-12 from the line.

Potential Finals preview: Every time the reigning champions take on a challenger, there’s going to be talk about a playoff matchup. That was indeed the case Wednesday as the Thunder are looking to take the next step. They’ve had successful regular seasons, including this year, but have yet to get back to the greatest stage in the sport. But that could change this year, and if the C’s are again able to navigate the East, there’s a good chance the Thunder could be waiting for them. But there’s still a lot of basketball left to be played before then. The Thunder have now swept the Celtics this season, including back in January in Oklahoma City. Of course, regular-season results don’t always translate to the playoffs.

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