Tobias Harris had to cut himself off.

“We want to be one of the best — we want to be the best defensive team in the NBA,” he said. 

After the Sixers’ 107-93 win over the Celtics Wednesday night in their season opener (see observations), one can understand why Harris felt the need to amend his statement.

The Sixers held Boston to 36.7 percent shooting from the floor, which would have been Boston’s worst shooting performance of the 2018-19 season. They limited Kemba Walker, who’d scored a career-high 60 points on them last year, to 12 points on 4 for 18 shooting.

Josh Richardson slithered around, through and over screens in pursuit of Walker. Rookie Matisse Thybulle took gamble after gamble, knowing what he termed as “the fine line” between intelligent risk and overextension could lean much closer to unencumbered aggression with big men like Joel Embiid and Al Horford waiting behind him. 

“It was intimidating at first,” Thybulle said of guarding Walker, noting he’s played as the three-time All-Star before in NBA 2K.

He made the transition from video game to reality well defensively, recording two steals and two blocks in his NBA debut.

Embiid during training camp compared Thybulle to Robert Covington, a First Team All-Defensive selection in 2017-18 and a starter for the Sixers on opening night last year against Boston.

 

Harris went further in his praise of Thybulle’s defense. 

“I have not seen a rookie come in with his defensive skills,” he said. “The only guy I would say is like Kawhi [Leonard] as a rookie — everybody knew he was a top defender.”

In Richardson, Horford and Thybulle, the Sixers have added three strong defensive players. And, for all his offensive value, they’ve subtracted a player opponents would often pick on in JJ Redick. 

Unlike last season, Jayson Tatum, Jaylen Brown and Gordon Hayward didn’t have a clear matchup to post up or isolate. Boston looked for advantages where they might reasonably exist, targeting Horford against perimeter players and putting pressure on Furkan Korkmaz, but it didn’t have much success. Just about everything the Celtics did on offense was effortful.

“We just tried to make it tough on them, every trip down,” Ben Simmons said. “They have a lot of talented guys, but we just tried to make sure they had tough shots. I think everybody did a solid job of that. Matisse made a lot of great plays on Kemba and he was great out there for his first game.”

The Sixers’ defensive performance was not flawless. They committed 34 fouls, more than in any regular-season game last year. Thybulle had five, including one in the second quarter when Walker got a step ahead of him and leaned back to create contact, finishing with an and-one. 

Those blemishes didn’t seem to bother Brett Brown.

“I’d rather water something down than demand it and keep harping on it,” he said. “If my problem is we’re playing that hard and we’re fouling too much, then I’ll take that on opening night. Inevitably, you can’t just whack people, stop the clock and we’ll send them to the line, and we did that way too much. I thought our feet were good, I thought our hands were poor, and it’s a good problem, I think, to have.”

Ime Udoka, the team’s new de facto defensive coordinator, said a month ago that he wants the Sixers to “make them feel you” and play a physical, attacking, flexible style. The variations in pick-and-roll coverage, occasional full-court pressure and different matchup possibilities might look complicated on the surface. At their core, though, those strategies all intend to dictate the way the game is played. 

Thybulle is still in the early stages of figuring out the NBA, but he has an intuitive understanding of that approach.

“Our goal going into the second half was just to impose our will,” he said, “and with our size and speed, athleticism, strength and everything, that was our goal — and we came out and did it.”

 

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