Jaylen Brown rescued the Celtics in Game 1 of the Eastern Conference finals.

In Game 2, he made sure no such heroics were necessary.

Brown poured in 40 points Thursday night to power Boston to a 126-110 victory over the Pacers at TD Garden. The comfortable win gave the Celtics a 2-0 lead in the best-of-seven series, which now shifts to Indiana for Game 3 on Saturday.

The sensational performance by Brown — whose 3-pointer with 5.7 remaining forced overtime in Game 1 — came one day after the Celtics star was left off the All-NBA third team, finishing one spot below the voting cutoff. His 40 points tied his playoff career high.

Derrick White scored 23 points and was 4-for-8 from 3-point range for Boston. Jrue Holiday added 15 points on 6-of-7 shooting and dished out nine assists. Those outings helped offset a relatively quiet offensive night for Jayson Tatum, who finished with 23 points, six rebounds and five assists.

Celtics backup center Luke Kornet left the game with a sprained wrist during the second quarter and did not return. With Boston already down starting big Kristaps Porzingis (calf strain), who reportedly is expected to miss at least one more game, Kornet’s status will be worth monitoring as the series moves to the Midwest.

Losing Kornet did create a role for backup forward Oshae Brissett, who saw the first meaningful postseason action of his NBA career. The ex-Pacer scored just two points but had three steals and was a plus-18 in 12 minutes, making a strong case for a more consistent role moving forward.

Pascal Siakam scored 28 points for Indiana on 13-for-17 shooting, but the Pacers got just 10 points out of All-Star point guard Tyrese Haliburton, who exited after 28 minutes with left hamstring soreness.

Brown paced Boston’s offense during an evenly matched first quarter, scoring seven of his team’s first nine points. Payton Pritchard added five first-quarter points in his first four minutes off the bench.

Indiana shot the ball much more efficiently than Boston did in the early going but led by just two after one quarter, 27-25.

The reason for that narrow deficit? Second-chance points. The Celtics grabbed six offensive rebounds in the first quarter to the Pacers’ zero, making up for some spotty shooting.

That trend continued early in the second, with Brown and Al Horford grabbing three offensive boards on a single possession. Brown finished it with an up-closer jumper that put Boston back ahead.

Then, the Pacers’ shooting went cold, and the Celtics capitalized. Indiana’s first 10 possessions of the second quarter ended in either a missed shot or a turnover, and Boston scored the first 17 points of the frame as part of a 20-0 run.

But Indiana, which responded well after Celtics scoring binges in Game 1, followed with its own 8-0 run and played Boston to a stalemate the rest of the half. The Celtics led 57-51 at halftime, with Brown accounting for 24 of their points.

Head coach Joe Mazzulla experimented with some new lineup combinations in the second quarter — perhaps out of necessity following Kornet’s injury. Brissett checked in for his first non-garbage-time minutes of the playoffs, and Boston went small for the final 2:30 of the half, sending out Sam Hauser alongside starters White, Holiday, Brown and Tatum.

That setup produced two quick buckets from Brown but struggled to defend Siakam, who scored on four straight Pacers possessions to close out the half. Boston led 57-51 at the break.

Tatum scored just four first-half points but began to assert himself in the third quarter. The first-team All-NBAer drove for a dunk, sank a step-back jumper a minute later and then zipped a drive-and-kick pass to Brown for a corner three.

This was Brown’s show, though. On the next Celtics possession, he drove and flipped a midair pass to a trailing Brissett for a dunk that prompted a Pacers timeout. Then, out of that stoppage, Brown stripped TJ McConnell at the top of the key and sprinted away for a fast-break slam.

The Celtics also took advantage of defensive breakdowns by Indiana that led to wide-open 3-pointers by Pritchard and Holiday. By the time the third quarter concluded, the game resembled most of the ones Boston has played this postseason: lopsided in favor of the C’s.

It was the first Game 2 victory of the playoffs for Boston, who lost at home to Miami and Cleveland in the first two rounds. They’ll look to take a commanding 3-0 lead Saturday night at Gainbridge Fieldhouse.