HOUSTON -- Facing the specter of a third consecutive series loss and a somber flight to Chicago, the Houston Astros accomplished something on Sunday that appeared wholly improbable given their debilitating injuries and continuing stretch of mediocrity since the All-Star Game break.

Third baseman Alex Bregman drilled a two-run, game-tying triple with two outs in the ninth inning before catcher Juan Centeno followed with a walk-off single to right field as the Astros rallied for an unexpected 7-6 victory over the Toronto Blue Jays at Minute Maid Park.

The Astros tallied four runs off Blue Jays closer Roberto Osuna (3-3) in their last at-bat. Jose Altuve, Yuli Gurriel and Marwin Gonzalez all singled during a four-batter stretch to load the bases, and Carlos Beltran followed with a run-scoring fielder's choice that cut the deficit to 6-4.

Bregman added his triple to left-center field, his eighth consecutive game with an extra-base hit, scoring Gurriel and the 40-year-old Beltran from first. Centeno lofted a line drive over the outstretched glove of leaping Toronto first baseman Justin Smoak to complete the comeback.

"It's nice to end the homestand on a better note than we've been playing," Astros manager A.J. Hinch said. "Obviously just a big win."

The Astros (71-40) appeared down for the count after Smoak capped a stunning four-run rally with a two-out, two-run double to straightaway center field in the seventh inning.

Smoak scored Russell Martin and Josh Donaldson with his hit, which turned around center fielder Jake Marisnick, off right-hander Luke Gregerson. Earlier in the seventh, Norichika Aoki drilled a two-run home run into the home bullpen off Astros starter Mike Fiers for a 4-3 lead.

Right-hander Marcus Stroman pitched into the seventh for the Blue Jays (52-59), allowing three runs (two earned) on 11 hits and two walks with six strikeouts over 6 2/3 innings. He departed just prior to the tying run coming to the plate in the form of Bregman, but Blue Jays right-hander Dominic Leone relieved and got Bregman to fly out to snuff that threat.

"I think I battled all game," Stroman said. "That's an unbelievable lineup over there, 1-9, and Altuve is extremely special. They have a few big bats out, but the guys that have stepped in are unbelievable as well. They put up 11 hits on me, but I was able to execute and get groundball outs when I needed to."

Fiers breezed for a stretch but was hurt by the long ball, allowing a pair of two-run homers, the first a Jose Bautista blast, his 17th, to left field for a 2-0 Blue Jays lead in the third inning.

The Astros rallied for three runs off Stroman in the fifth, with Altuve, Gurriel and Gonzalez recording RBIs. But when Leone put out the fire in the seventh and retired the side in order in the eighth, the Astros looked defeated. The ninth inning was a different story altogether.

"We didn't have the best homestand, we didn't have the homestand that we wanted to but hopefully this gives us a little energy on the road," Bregman said. "We just have to keep doing what we're doing. We're 31 games above .500. There's going to be ups and downs throughout the season, we just need to stay the course ... and keep going out there and competing."

Right-hander Francis Martes (4-1) worked 1 2/3 scoreless innings and earned the victory in relief for the Astros, who claimed the rubber match of the series.

"You don't think they're going to score three or four, but it happens," Blue Jays manager John Gibbons said. "When things get rolling, they don't let you up. It's a deep lineup, they got caught up in it and they got some big hits."

NOTES: Astros RF Josh Reddick was presented the Heart and Hustle Award as the Astros representative for an honor bestowed to a player from each team by the MLB Players Alumni Association. The award recognizes active players who demonstrate a passion for the game and best embody the values, spirit and traditions of the game. ... Blue Jays LF Norichika Aoki made his first start since being acquired from the Astros on July 31 at the non-waiver trade deadline. He finished 1-for-4 with three strikeouts and a go-ahead, two-run homer. ... Astros OF George Springer will make the trip to Chicago with the club and could be reinstated from the 10-day disabled list on Tuesday. Springer was placed on the DL on July 25 with left quad discomfort.