MEMPHIS -- The Los Angeles Lakers entered the fourth quarter of Sunday's Game 1 of their first-round series against the Memphis Grizzlies clinging to a six-point lead.

In the first 11 minutes of the final frame, LeBron James and Anthony Davis attempted just one shot apiece.

And yet L.A. ran away with a 128-112 victory as a bench player and a guy who went undrafted out of college just two years ago took over.

Rui Hachimura scored nine of his 29 points in the fourth, tying Mychal Thompson's Lakers franchise record for most points by a substitute in a playoff game. Austin Reaves went 5-for-5 in the fourth, including scoring nine straight points late in the quarter, en route to 23 points total.

"It was our supporting cast that won us the game tonight," said James, who had 21 points, 11 rebounds and 3 blocks.

The Lakers needed the extra effort from their roster with things looking dicey at halftime. Davis, who finished with 22 points, 12 rebounds, 7 blocks and 3 steals to become the first player since Tim Duncan nearly 20 years ago to put up that type of postseason statline, suffered a stinger to his right shoulder and had to exit the game late in the second quarter.

The Lakers trailed by six at the time.

Then Hachimura went 4-for-4 from 3 in six minutes of playing time in the third quarter and L.A. was back in control. The fourth-year forward, acquired in a trade with Washington in late January, said they were all shots he specifically practiced coming into the series, with Lakers assistant coach Phil Handy scouting the gaps in the Grizzlies' defense that Hachimura could target.

"The way they guard me, they're going to be in the paint so I got to be ready to shoot those kind of shots," Hachimura said.

Grizzlies guard Desmond Bane confirmed as much, while directing a challenge toward Hachimura for Game 2.

"That was our game plan going in -- make him hit shots and he did," Bane said. "Tip your cap. It's probably the best game he's had in his career. It's a seven-game series. Let's see if he can do it again Wednesday."

Reaves, who signed a two-way contract with the Lakers in the summer of 2021 after he went undrafted out of Oklahoma and was later converted to a full-fledged member of the team before the season began, closed things out.

"You dream about being on a stage like this," Reaves said. "And I got hot late and I had fun."

It was the first time the Lakers had four players score 20 or more in the playoffs since May 15, 1988, when James Worth, Magic Johnson, Kareem Abdul-Jabbar and Byron Scott did it. And D'Angelo Russell (19 points, seven assists) nearly made it five.

While L.A. won 10 of its past 12 games, including Tuesday's play-in win over Minnesota to secure the No. 7 seed against No. 2 Memphis, there were signs of slippage. The Lakers didn't look sharp in their final four regular-season games, which included a loss to the Clippers, and their effort against Minnesota was disjointed at best and undisciplined at worst.

Lakers coach Darvin Ham said his team used the four-day break between the win over the Wolves and Game 1 against Memphis to recalibrate.

"The last week of the season or so, the play-in game, possessions got away from us," Ham said. "We threw away possessions with no pass or one pass and then shot."

L.A. locked in after a team address by James and Davis about the increased intensity that the playoffs require, and seemingly has recaptured the momentum that got it to the playoffs in the first place.

"How can we best extract the most production as we can out of this group?" Ham said, explaining the aim of the time off. "And this is how. This is what's going to work against this team and what we need to explore; this is what we need to leave to the side. I thought it was a combination of all of that -- being fresh and taking a deep, hard look at our offense and what's been good and what's been bad."

While the Lakers started the series off with a statement win, stealing home-court advantage from the Grizzlies as they attempt to become the first No. 7 seed to pull off a first-round upset since San Antonio in 2010, James focused on some of the bad from Sunday. He pointed out that L.A.'s 16 turnovers led to 15 points for the Grizzlies and took responsibility for the five he had himself.

"I thought the guys definitely understood that assignment and were really good tonight," James said. "But I think we can be even better."