The rookie came off the bench to play left field during the eighth inning against the Miami Marlins on Saturday night and then delivered a three-run homer in the bottom of the inning to break a tie as the Dodgers recovered for a 10-6 victory after blowing a six-run lead.
"He's taking care of what he needs to take care of. He has come up with some big hits for us," manager Dave Roberts said.
Beaty's drive to right-center on a changeup by Elieser Hernandez (1-4) bailed out the Dodgers' bullpen and defense. Los Angeles led 6-0 through six innings after Clayton Kershaw had a season-high 10 strikeouts and allowed only two hits. Joc Pederson and Justin Turner provided the early lift on offense with home runs before the Marlins rallied to tie.
"I got that one pretty good. I was looking for a pitch out over the plate that I could drive," said Beaty, who is 14 for 31 with three home runs and 21 RBI with runners in scoring position.
Roberts said Beaty will be in the starting lineup for Sunday's finale of the three-game series.
Miami took advantage of a Los Angeles bullpen that has struggled in middle relief and benefited from a pair of errors in a five-run eighth.
Jorge Alfaro nearly had a grand slam but Alex Verdugo made a great catch at the base of the wall in right to keep it a sacrifice fly. Brian Anderson's two-run double off Yimi Garcia -- the third of four Dodgers pitchers used in the inning -- brought the Marlins within 6-4 before they tied it on a throwing error by second baseman Enrique Hernandez, which allowed Anderson to score.
"It was a tale of two different games. Early on Kershaw had us on our heels then all of a sudden we catch some breaks and get some big hits," Marlins manager Don Mattingly said.
The Dodgers, who had three errors in the game, have committed 20 in July, which is the most in the majors and becoming a growing concern for Roberts.
"I can't remember the last time we played a clean game," he said. "The relievers have to get better at throwing quality strikes. If something does happen where a play is not made we have to be able to overcome that."
Kershaw said he was disappointed not to get the win but defended the bullpen.
"We've got guys with good stuff," he said. "It's not any different from a starting pitcher going through a rut. We're just going to have to find that consistency."
Pederson, who came into the game 4 for 22 since the All-Star break, hit a line-drive shot over the short wall in right off Sandy Alcantara to lead off the first.
Los Angeles added three in the fourth on Austin Barnes' two-run double and an RBI single by Kershaw. The next inning, Turner hit a solo shot over the wall in center and Max Muncy added an RBI double to make it 6-0.
After Beaty's home run, Russell Martin provided added insurance with a pinch-hit RBI single.
Fernando Valenzuela was inducted into the "Legends of Dodger Baseball" before the game.
STREAKS, STATS AND NOTES
The Dodgers improved to 39-12 at Dodger Stadium. That equals the 2017 team for best home start after 51 games in franchise history. ... Alcantara went five innings and allowed six runs on seven hits. ... Seager had three hits. ... Castro is 21 of 58 with three home runs and eight RBI in July.
Marlins: SS Miguel Rojas was taken out during the fifth inning due to a strained right shoulder.
Dodgers: LHP Rich Hill (forearm strain) has started a throwing program with the possibility of returning sometime in September. ... LHP Scott Alexander, who is on the IL with left forearm inflammation, is also dealing with a nerve problem in his left thumb with no timetable on a return.
Marlins: RHP Jordan Yamamoto (4-0, 1.59 ERA) faces the Dodgers for the first time. He is holding opponents to a .134 batting average, which is the lowest in the majors since June 12.
Dodgers: RHP Walker Buehler (8-1, 3.44 ERA) makes his third career start against the Marlins. He has no record and a 3.60 ERA.
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