Work with NBA "Shot Doctor'' Chip Engelland is paying off for Josh Giddey, who again flourished offensively as an undermanned Oklahoma City briefly threatened title favourites Boston.
Giddey (17 points on 64 per cent shooting) top-scored for a Thunder team missing MVP candidate Shai Gilgeous-Alexander (quad) and Jalen Williams (ankle).
The Australian's third-quarter surge helped make it a five-point game before the runaway Eastern Conference leaders shot to safety and secured the No.1 seeds with a 135-100 win.
Giddey added six rebounds and two assists and boasted a team-best differential of negative two in the 35-point loss in Boston.
It continued his offensive resurgence that has been credited in part to work with OKC assistant Chip Engellend.
Engellend has worked as an NBA assistant since 1999 and was at San Antonio for 17 years before joining the Thunder in 2022.
He was credited with adjusting Kawhi Leonard's shot, and was at the club when Australians Patty Mills and Aron Baynes won a championship 10 years ago.
Giddey's confidence attacking the rim was obvious at TD Garden, the 21-year-old shooting at 58 per cent from the field or better in seven of his past eight games.
His form, particularly on offence, is well-timed considering he will be asked to shoulder much of the load for the Boomers at the Paris Olympics from July.
"What a feeling that is as a player to rediscover your mojo. Josh Giddey has his mojo right now," former player turned pundit JJ Redick said.
Kristaps Porzingis had 27 points, 12 rebounds and five blocked shots for the high-flying Celtics (60-16).
The Thunder (52-24) remain third in the West with six regular-season games to play, but have secured a return to the play-offs after a three-year absence.
Elsewhere, Australian veteran Joe Ingles scored four points and added three rebounds, two assists and two steals as Orlando won 117-108 on the road in New Orleans.
That was despite 16 points, including four-of-five triples, from in-form compatriot Dyson Daniels, who also added three assists and two steals for the Pelicans.
Boomers forward Duop Reath had seven points for Portland, who edged the Hornets 89-86 in Charlotte to snap a 10-game losing streak.
Cam Thomas scored 27 points, rookie Noah Clowney had a career-high 22 and Brooklyn, already out of post-season contention, outlasted Indiana 115-111.
Anthony Davis scored 19 of his 35 points in the first quarter and had 18 rebounds, helping the Los Angeles Lakers beat Washington 125-120 for their eighth victory in nine games.
LeBron James had 25 points and nine assists, and Rui Hachimura scored 19 points for the Lakers against his former team.
Minnesota pulled away for a 133-85 win over Toronto behind Anthony Edwards' 28 points, while Devin Booker scored 40 in Phoenix's 122-101 win over Cleveland.
And Jalen Johnson recorded the first triple-double of his career as Atlanta clinched a spot in the play-in tournament with a 121-113 win over the visiting Detroit.
With AP, Reuters
