TORONTO -- The Seattle Mariners and the Toronto Blue Jays have the next four games to compare injury woes.

The Mariners' problems begin with the fact that their scheduled starting pitcher for series opener Thursday, Hisashi Iwakuma, was put on the disabled list Wednesday due to shoulder inflammation.

Chase De Jong (0-2, 6.75 ERA), originally scheduled to start Friday, was moved to Thursday, and he will face Marco Estrada (1-2, 3.14 ERA).

The Mariners now have four members of their rotation on the DL, with Iwakuma joining Felix Hernandez (shoulder bursitis), Drew Smyly (flexor strain) and James Paxton (forearm strain).

Yovani Gallardo is the only member of the projected rotation still in action. He allowed three runs in five innings and did not factor in the decision as the Mariners defeated the Phillies 11-6 on Wednesday afternoon in Philadelphia.

The Mariners, who have won four in a row, will get little sympathy from the Blue Jays, who have two starting pitchers on the disabled list: J.A. Happ (elbow) and Aaron Sanchez (blister, split nail). Sanchez could return Sunday to face the Mariners.

Shortstop Troy Tulowitzki (hamstring), third baseman Josh Donaldson (calf) and catcher Russell Martin (left shoulder) also are on the DL for Toronto (13-21).

That did not stop the Blue Jays from winning a second straight series for the first time this season on Wednesday. They came back to defeat the Cleveland Indians 8-7 on a walk-off single by Ryan Goins, who has done admirably replacing Tulowitzki.

"Similar games we were losing earlier in the season," Blue Jays manager John Gibbons said. "The guys in that room understand we have a lot of injuries and it's their chance, and they're kind of feeding off that. Things have kind of flipped in the month of May; we're starting to win some of those game we couldn't win earlier in the year."

Gibbons said of Goins, "I think it's just the fact that he's out there a lot. We told Tulo that he's Wally Pipping him and that could delay his rehab. Ryan has a ton of confidence; he's done a hell of a job. He's got some big, big hits in the month of May."

After going 8-17 in April, the Blue Jays are 5-4 in May. When they face the Mariners, they will be trying to win two games in a row for only the third time this season.

The Mariners (17-17) must find a different way to win with 80 percent of their rotation injured. They scored 21 runs on 32 hits in sweeping two games from the Phillies, moving to .500 for the first time this season.

"That's kind of the formula for us right now," Seattle manager Scott Servais said. "Have our starter keep us in the game, go to the bullpen ... and maybe shorten the game a little bit and keep it tight enough where our offense can figure it out. It's worked out well."

The Mariners have won six of their past seven games.

"It's a day at a time," Servais said. "If you start saying, 'Oh, we've got to win seven out of 10,' it gets too confusing. Our guys -- tip my hat to them -- they have not gotten down even with the early struggles."

Estrada took the loss Saturday at Tropicana Field in the Tampa Bay Rays' 6-1 victory, allowing six hits, two walks and five runs while striking out seven in six innings. He gave up two homers. All five of the home runs he has allowed this season have been at Tropicana Field. He is 1-3 with a 4.13 ERA in four career games (all starts) against the Mariners.

De Jong was a second-round draft pick by the Blue Jays in 2012. He was traded to the Los Angeles Dodgers, who sent him to the Mariners earlier this season.

In two starts at Triple-A Tacoma this season, he was 2-0 with a 1.74 ERA. In his most recent major league start, on Saturday, he allowed four hits and one run against the Texas Rangers in a no-decision during a game won 8-2 by the Mariners. He has never faced the Blue Jays.