Shaky relief from Oakland's Trevor May in the ninth inning led to Kirby Snead (1-1) coming on and issuing a two-out, bases-loaded walk to Dominic Smith before shortstop Nick Allen's error led to two runs to tie the game. Downs, who began the inning with a walk, won the game with a single to centre field.
Zack Gelof hit solo home runs in the first and fifth innings and racked up four hits, but the Athletics lost for the ninth time in their last 12 games. Seth Brown also homered and drove in four runs for Oakland.
Joe La Sorsa (1-0) pitched two shutout innings for the victory - his first in the majors.
Marlins 8, Yankees 7
Jake Burger hit a game-ending single with one out in the ninth inning as Miami rallied for a victory over the visiting Yankees.
The Marlins got their eighth walk-off win by rallying for five runs in the ninth against Clay Holmes (4-3) and Tommy Kahnle. Holmes committed a two-run throwing error on a comebacker by Josh Bell, and Bell scored from first base when Luis Arraez lined a game-tying, two-run triple down the right field line.
Before the collapse, rookie Anthony Volpe hit a two-run homer and Ben Rortvedt hit a solo homer to help the Yankees build a 7-1 lead through 5 1/2 innings.
Orioles 5, Mariners 3 (10 innings)
Cedric Mullins hit a two-run homer with one out in the 10th inning as Baltimore defeated hosts Seattle in extra innings for the second straight day.
The Mariners' streak of winning six straight series came to an end. Orioles reliever Nick Vespi (1-0) got the victory, and Shintaro Fujinami earned his first major league save. Seattle's Trent Thornton (0-1) took the loss.
After Baltimore broke a 2-2 tie in the top of the ninth, the Mariners again knotted the game on Dominic Canzone's solo home run with two outs in the bottom of the inning. The bomb came just after Mullins made a leaping catch in center field to rob Ty France of a homer.
Giants 3, Rangers 2 (10 innings)
Patrick Bailey lined a two-out, two-run home run in the bottom of the 10th inning, allowing San Francisco to escape a wild finish with a walk-off victory over visiting Texas.
Attempting to get their manager, Bruce Bochy, a three-game sweep in his San Francisco homecoming, the Rangers rallied from down 1-0 in the ninth to draw even in regulation and then went ahead 2-1 in the top of the 10th on a Camilo Doval balk. Doval (4-3), who was docked with his fourth blown save in the ninth, was credited with the win.
Rangers closer Will Smith (1-4) got the first two outs in the last of the 10th with automatic runner Wilmer Flores anchored to second base before Bailey lashed his sixth homer of the season over the fence in left field.
Dodgers 8, Rockies 3
Julio Urias tied a career-high with 12 strikeouts and Miguel Rojas drove in four runs and hit a go-ahead home run as the Dodgers finished off a four-game sweep of visiting Colorado.
Mookie Betts had a two-run double as they won their season-high eighth consecutive game. They've also won 12 of their last 13 and are a major-league-best 20-8 in the second half. Urias (10-6) gave up three runs on four hits over seven innings with no walks as he won his third consecutive start.
Alan Trejo hit a two-run home run for the Rockies while left-hander Kyle Freeland (4-13) saw his winless streak extend to 14 consecutive starts. Freeland moved into a tie for the major league lead in losses.
Blue Jays 11, Cubs 4
Daulton Varsho hit a three-run home run and had a career-best five RBIs as Toronto ended a three-game losing streak by beating the visiting Cubs.
Vladimir Guerrero Jr. added two RBI singles and Whit Merrifield had four hits, drove in a run and stole a base for Toronto. Winning pitcher Hyun Jin Ryu (1-1) allowed two unearned runs, two hits and two walks in five innings. It was his third start after coming back from elbow surgery.
Patrick Wisdom hit a two-run home run for the Cubs, who won the first two games of the three-game series. Right-hander Jameson Taillon (7-7) allowed eight runs, eight hits and two walks in three-plus innings.
Angels 2, Astros 1
Rookie right-hander Chase Silseth remained unbeaten over his last four starts while Shohei Ohtani clubbed his American League-leading 41st home run as the Angels salvaged the finale of a three-game series with a win over host Houston.
Ohtani ended an eight-game homerless drought by drilling a 1-0 slider from Astros left-hander Parker Mushinski 448 feet to straightaway centre field with two outs in the sixth inning, doubling the Angels' lead to 2-0. Silseth (4-1) allowed four hits and two walks with five strikeouts over five scoreless innings.
Astros starter Jose Urquidy pitched well in his second start following a three-month stint on the injured list with right shoulder discomfort. He allowed one run on three hits and did not issue a walk while recording seven strikeouts over five-plus innings.
Red Sox 6, Tigers 3
Adam Duvall homered and drove in four runs and Trevor Story had four hits to lead Boston past visiting Detroit.
Justin Turner, who was playing in his 1,500th major league game, also went deep for the Red Sox. It was his 19th home run of the season and his second in as many games. Duvall and Turner each had two of Boston's 12 hits.
Akil Baddoo launched a solo home run in the fifth inning for the Tigers, who lost twice in the three-game series.
Twins 3, Phillies 0
Sonny Gray tossed six shutout innings as Minnesota beat hosts Philadelphia in the rubber match of their three-game series.
Gray (6-5) lowered his ERA to 3.04 after giving up just two hits en route to his fifth consecutive quality start. Jordan Luplow homered and Jorge Polanco had a pair of RBI singles for Minnesota.
Polanco's run-scoring single provided the Twins with an insurance run in the top of the ninth, and Jhoan Duran worked the bottom of the inning for his 21st save. Philadelphia wasted a stellar outing from Ranger Suarez (2-6), who gave up two runs on six hits in 6 1/3 innings.
Pirates 4, Reds 2 (Game 1)
Jared Triolo's pinch-hit, three-run homer in the seventh inning gave Pittsburgh a win over visiting Cincinnati in the first game of a doubleheader.
Alika Williams added an RBI single for the Pirates. Pittsburgh starter Mitch Keller allowed two runs (one earned) and five hits in six innings. Angel Perdomo (3-2) pitched a scoreless seventh to earn the win, and David Bednar pitched the ninth for his 24th save.
Matt McLain hit an RBI double and Christian Encarnacion-Strand had an RBI single for the Reds. Cincinnati starter Brandon Williamson pitched 5 2/3 innings, giving up one run and two hits. Losing pitcher Alex Young (4-1) gave up two runs in one inning.
Reds 6, Pirates 5 (Game 2, 10 innings)
Stuart Fairchild's forceout drove in Tyler Stephenson in the 10th inning to give visiting Cincinnati a win over Pittsburgh and a split of the twin bill.
Stephenson was the pinch runner for the automatic runner to open the inning against Osvaldo Bido (2-3). With one out, Stephenson took third on TJ Hopkins' single and scored on Fairchild's grounder. Elly De La Cruz added a home run for the Reds.
Alexis Diaz (4-4) pitched 1 2/3 scoreless innings. Daniel Duarte got his first career save. Bryan Reynolds homered twice and Liover Peguero homered and hit an RBI single for the Pirates.
Guardians 9, Rays 2
Andres Gimenez collected four hits, including a home run, and Oscar Gonzalez chipped in with three doubles to power Cleveland to a win over Tampa Bay in St. Petersburg, Fla.
Tanner Bibee (9-2) held the Rays in check, giving up two runs on seven hits with five strikeouts in seven innings. Gabriel Arias added a home run for the Guardians.
Rays starter Zach Eflin (12-7) surrendered a season-high six runs in just three innings. In the bottom of the third, Rays shortstop prospect Osleivis Basabe, making his major debut, doubled in his first big-league at-bat. Yandy Diaz's RBI single plated Basabe for the Rays' first run.
Brewers 7, White Sox 3
Freddy Peralta pitched six shutout innings and Carlos Santana hit a three-run home run as visiting Milwaukee defeated the White Sox to secure a three-game sweep.
Peralta (9-8) won his third straight start, scattering four hits - all singles - while walking three and striking out six. The Brewers won their fourth straight game overall, stretching their lead in the National League Central to 3 1/2 games.
Carlos Perez delivered an RBI double with two outs in the ninth to help the White Sox avoid the shutout. Elvis Andrus added a two-run single to account for the final margin. Andrew Vaughn singled three times to pace the White Sox, who have lost four of their last five.
Diamondbacks 5, Padres 4
A two-run home run by Lourdes Gurriel Jr. in the seventh inning helped Arizona come back from a three-run deficit and beat San Diego in Phoenix.
Arizona have won consecutive games after losing nine straight and earned their first series win since winning two out of three games against the Atlanta Braves on the road from July 18-20. San Diego have lost six of their last seven games.
After Gurriel's two-run home run tied the game at 4, the Diamondbacks took the lead in the eighth on a sacrifice fly by Alek Thomas. Kyle Nelson (6-3) won in relief and Paul Sewald earned his 23rd save. The Padres had held a 3-0 lead in the first inning.
Mets 7, Braves 6
Kodai Senga survived a rocky first inning to toss six solid frames and earn the win for hosts New York, who salvaged the finale of a four-game series by edging Atlanta.
Senga (9-6) gave up three runs on four hits and two walks while striking out seven. Rafael Ortega had three hits, including a two-run single to cap a fifth inning in which the Mets scored six times while sending 11 batters to the plate.
Sean Murphy homered in the seventh and Matt Olson added a two-run shot in the eighth for the Braves before Adam Ottavino recorded his seventh save with a 1-2-3 ninth. Atlanta starter Yonny Chirinos (5-5) allowed six runs on seven hits.
