Tyler Herro helps Heat to 3-1 series lead vs. Celtics in Eastern Conference finals

LAKE BUENA VISTA, Fla. — Tyler Herro had his coming-of-age playoff moment in Game 4 of the Eastern Conference finals.

The Miami Heat relied on the bull's-eye shooting of their rookie guard, who delivered with a career-high 37 points in Miami’s 112-109 victory over the Boston Celtics on Wednesday.

Herro, who became the youngest player to score 30 or more points in a conference finals, shot 14-for-21 from the field, including 5-for-10 on 3-pointers. He had 15 points in the first half, 22 in the second half and also had six rebounds and three assists in helping Miami to a 3-1 series lead.

Herro’s total — 17 points came in the fourth quarter — was also the most playoff points for a rookie in franchise history and the most for a rookie in a conference finals game.

"He's not a rookie anymore," Heat coach Erik Spoelstra said. "We need his skillset. Does that mean it's going to translate into that kind of point production every night? No, it doesn't. I mean, we're not necessarily built like that. ... Tyler is able to generate a lot of offense on random situations, which you need against a very good defense."

Game 5 is Friday (8:30 p.m. ET, ESPN), and the Heat are one victory from advancing to the NBA Finals for the first time since 2014.

Miami led for much of the game, but Daniel Theis’ dunk made it 85-84 Celtics with 8:51 left in the fourth quarter, giving Boston its first lead since early in the second quarter.

But down the stretch, Herro hit a pair of key 3-pointers, including one from 29-feet out, putting Miami up 98-90 with 4:09 remaining. His reverse layup on an assist from Jimmy Butler made it 107-98 with 56.2 seconds left, and free throws by Herro and Butler secured the victory.

Butler had 24 points and nine rebounds, Bam Adebayo added 20 points and 12 rebounds and Goran Dragic finished with 22 points. Those four combined for 103 of Miami’s 112 points.

"You have to find a way to grind out a win at the end by any means necessary," Spoelstra said. "(Wednesday) was an example of that. A lot of guys contributed and put their fingerprints on it, not just from the offensive end. Defensively, making a lot of efforts.

"Bam was tremendous on the offensive glass, getting us some extra possessions. Jimmy got a relief pull-up jumper. Goran hit that big three and Tyler was generating a ton of offense for us in that second half. But you need that. You're going to need it. Probably even more of that the next game."

Boston shot 47.6% from the field but also committed 19 turnovers. Jayson Tatum scored his 28 points in the second half, Kemba Walker had 20 points and Jaylen Brown had 21.

Miami mixed up its defensive coverages, going to a zone on some possessions. The zone defense has gained some popularity in the playoffs. Toronto used it against Boston in the conference semifinals, Miami has used it against the Celtics and the Los Angeles Lakers puzzled Denver in Game 3 with it.

After Miami’s Game 2 victory in the conference finals, Celtics coach Brad Stevens said, “It's a hard zone to play against. We did play well against it in Game 1. We played with way better pace than we did tonight. So we'll go back and look at it, figure out if it was a technical thing or a pace thing or an execution thing or just not-as-focused-on-the-important-stuff thing.”

It took the Celtics some time but they began to crack the zone with dribble penetration and solid back-screens. Tatum really found his offense in the second half, but the Celtics struggled with the zone late in the game.

"It's easy for me to say be tough with the ball, be strong with the ball," Celtics coach Brad Stevens said. "Those guys are tremendous with their hands when you put (Andre) Iguodala and Jimmy at the top of that zone. We got to do a better job of handling the ball. We got to do a better job of taking care of it."

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The first half was not pleasant on the eyes. The Celtics made just 5-of-19 3-pointers, and the Heat made 4-for-17.

Tatum missed his six shot attempts, including four 3-pointers, and committed three turnovers in the first two quarters. Marcus Smart was 2-for-7, Gordon Hayward 1-for-5 and Brown had four turnovers in a bad opening two quarters.

"It's hard to win a playoff game, right?" Stevens said. "It's hard to win a playoff game both ways. We're just looking at how can we play better Friday night. That's the most important game of the season. We need to play our best game yet. That's it."