Jimmy Butler on track to accomplish a Heat first. Also, a Heat-Celtics injury update

Jimmy Butler is on track to do something no other player in Miami Heat history has accomplished.

Butler entered Sunday afternoon’s matchup against the Boston Celtics at TD Garden averaging a league-leading and career-high 2.1 steals per game with just one week remaining in the regular season. Indiana Pacers guard T.J. McConnell is second in this category, averaging 1.8 steals per game.

Butler, 31, would become the first Heat player in franchise history to finish a season as the NBA’s steals leader.

“I think you gotta look at who has the ball,” Butler said of his knack for racking up steals. “Right-hand or left-handed, what their skill set is and I guess some good timing. Some timely gambles.”

Even if Butler doesn’t record another steal, McConnell would need to record about 29 total steals over the Pacers final five regular-season games, or an average of about 5.8 steals per game during that span, to come close to catching Butler.

In other words, there’s a very good chance Butler will end the regular season as the NBA’s steals leader.

Butler entered Sunday with 105 steals this season. He has finished with at least 100 steals in eight consecutive seasons, tying Brooklyn Nets guard James Harden for the longest active streak in the NBA.

“He has very disciplined gambles,” Heat coach Erik Spoelstra said of Butler earlier this season. “I know that’s counterintuitive. But I’ve coached players that will totally take themselves out of a play. Jimmy is a very disciplined team defender. ... When he’s on the weak side, he just has a knack. It’s those timely plays. It’s super high IQ and that cat quickness that he has that you can’t teach that he’s just first to the ball. That surprises everybody, I’m sure it surprises the passer. They’re unpredictably creative. So it’s not necessarily something that, OK this is a tendency that you can prepare for. It’s just the in-the-moment, his greatness is able to make some of those steals and reads that are uncommon.”

While Butler is on pace to finish as the league’s steals leader this season, he’s a bit off the pace needed to average the most steals by a Heat player in franchise history. Dwyane Wade set that record when he averaged 2.2 steals per game in the 2008-09 season.

Butler, who has made the NBA’s All-Defensive second team four times in his career, does more than just jump passing lanes, though. He’s also an elite on-ball defender, as players entered Sunday shooting 43.2 percent this season with Butler defending them — 2.9 percent worse than their overall shooting percentage, according to NBA Advanced Stats.

The Heat has allowed opponents to score at a pace of 106.7 points per 100 possessions with Butler on the court, compared to 112.4 points per 100 possessions when he hasn’t been on the court this season.

Butler’s ability to collect steals is a big reason why the Heat has been one of the NBA’s best at forcing teams into turnovers. Miami entered Sunday with the league’s second-highest opponent turnover percentage, with Heat opponents committing a turnover on 15.8 percent of their possessions, according to Cleaning the Glass.

“There’s a lot of incredibly unique things about JB as a defender and a lot of them may be contradictory,” Spoelstra said Sunday. “Because I think the fans maybe see the ‘leading the league in steals’ and you see the picks and some of the trickery where he’s in a passing lane that you don’t even see it before it’s happening, and he has great anticipation and closing speed. But he’s also an old school just line him up against the other team’s best player, mano a mano, and take that challenge.

“Whatever your defensive schemes may be, he’s very disciplined and he has been true to that in all the defensive systems that he has been in over the course of his career. He has been able to adapt and find a way to make an impact.”

INJURY UPDATE

The Celtics will be missing one of their best players against the Heat. Boston All-Star wing Jaylen Brown has been ruled out for Sunday’s game because of a sprained right ankle.

It marks the third straight game that Brown has missed with the ankle injury. Brown is the only Celtics player unavailable Sunday.

The only Heat player unavailable for Sunday’s contest is guard Victor Oladipo, who will miss his 16th consecutive game with right knee soreness. Oladipo did not travel with the team to Boston.

Heat veteran Andre Iguodala, who was listed as questionable because of a right quad contusion, is available to play on Sunday.

The Heat and Celtics face off again in Boston on Tuesday night.