Corey Seager singled home Austin Barnes with the tiebreaking run in the eighth inning and the Los Angeles Dodgers beat the Seattle Mariners 2-1 on Tuesday for their seventh consecutive victory.

Barnes scored both runs for the Dodgers, who improved to an NL-best 18-7 and sent the Mariners to their seventh straight defeat.

The catcher walked and stole his first base of the season before Seager drove him in with a two-out drive through the shift in right.

Los Angeles Dodgers' Justin Turner, right, hits an RBI single with Seattle Mariners catcher Austin Nola, left, watching during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Los Angeles Dodgers' Justin Turner, right, hits an RBI single with Seattle Mariners catcher Austin Nola, left, watching during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

With the temperature at 102 degrees in Chavez Ravine for the opening pitch, Tony Gonsolin threw six scoreless innings of two-hit ball for the Dodgers. He had an impressive duel with Marco Gonzales, who struck out nine in seven innings of five-hit ball for the Mariners.

After the starters dominated early in scorching heat, Justin Turner had an RBI single in the sixth inning off Gonzales. Seattle tied it on Tim Lopes' RBI groundout in the seventh, rallying against the Dodgers' bullpen.

The Dodgers manufactured the go-ahead run against Dan Altavilla (1-2) with a timely steal by Barnes, a catcher who had only 12 stolen bases in his first five big league seasons.

Los Angeles Dodgers' Austin Barnes, center, collides with Seattle Mariners catcher Austin Nola, right, to score on a late throw to the plate on a single by Justin Turner during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Los Angeles Dodgers' Austin Barnes, center, collides with Seattle Mariners catcher Austin Nola, right, to score on a late throw to the plate on a single by Justin Turner during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

That set up the latest big hit by Seager, who homered in each of the Dodgers' two previous games.

Blake Treinen (2-1) got five outs on just 16 pitches for the win.

Gonsolin has yet to yield an earned run in three starts this season for the Dodgers, who didn't have him in their opening day rotation. He held the Mariners to two singles and no walks while matching the longest start of his career, striking out three and allowing no runners to reach third base.

Los Angeles Dodgers starting pitcher Tony Gonsolin throws to the plate Seattle Mariners during the first inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Los Angeles Dodgers starting pitcher Tony Gonsolin throws to the plate Seattle Mariners during the first inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Working quickly in the heat, Gonsolin became the first pitcher to start a season with three straight scoreless starts of at least four innings apiece for this 131-year-old franchise since Wheezer Dell, who did it for the Brooklyn Robins in 1916.

Mariners manager Scott Servais said he needed a significant start from Gonzales after using his bullpen heavily Monday, and Gonzales responded like the ace he is becoming.

The Dodgers finally broke through in the sixth when Barnes singled, advanced on a grounder and scored on Turner's single to left.

Los Angeles Dodgers' Austin Barnes, below left, slides in safely to second base as the throw from first arrives late to Seattle Mariners third baseman Kyle Seager, center, with shortstop J.P. Crawford backing up the throw, during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Los Angeles Dodgers' Austin Barnes, below left, slides in safely to second base as the throw from first arrives late to Seattle Mariners third baseman Kyle Seager, center, with shortstop J.P. Crawford backing up the throw, during the sixth inning of a baseball game in Los Angeles, Tuesday, Aug. 18, 2020. (AP PhotoAlex Gallardo)

Gonsolin was pulled before the seventh on 84 pitches, and Kyle Lewis drew a leadoff walk from Jake McGee before Kyle Seager doubled him to third. Lewis scored on a one-out groundout by Lopes.

Scott Alexander stopped the rally in the seventh, and he made a spectacular no-look, behind-the-back stop of Dee Gordon's drive back to the mound in the eighth.

MARINERS MOVES

After going deep in the bullpen Monday, Seattle recalled RHP Art Warren from the alternate training site and optioned OF Mallex Smith, who is batting just .133 this season. Warren made his major league debut with six relief appearances late last season.

TRAINER'S ROOM

Mariners: They transferred C Tom Murphy to the 45-day disabled list with a broken foot, sidelining him at least until September.

Dodgers: Rookie C Keibert Ruiz confirmed he was late to summer camp because he contracted COVID-19. He felt feverish and ill for three days, he said. Ruiz got called up last weekend to replace injured C Will Smith, and he homered on his first big league swing in Anaheim.

UP NEXT

Both clubs went from Dodger Stadium to the airport for the two-hour flight to Seattle, where the Mariners will send out Taijuan Walker (1-2, 4.05 ERA) on Wednesday night against Los Angeles' Julio Urías (2-0, 2.53).

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