TORONTO -- This was the Yusei Kikuchi the Mariners had been waiting to see over the past three months, the power left-hander who had looked so promising in the early going of his first season in the Majors.

The 28-year-old rookie from Japan fired a two-hit shutout in Sunday’s 7-0 victory over the Blue Jays at Rogers Centre, responding to rising questions and concerns after posting a 1-7 record and 7.50 ERA over his previous 14 starts.

• Box score

It was the first complete game for Kikuchi this season, with his previous longest start being 7 2/3 innings in a 10-1 win over the Yankees on May 8. He threw 15 complete games in eight seasons in Japan, but none were under 100 pitches.

This gem needed just 96 pitches, and it was a remarkable turnaround after Kikuchi lasted just 3 1/3 innings on Tuesday in Detroit, allowing nine hits and five runs on 81 pitches.

After discussions with Seattle’s pitching coaches and teammates Marco Gonzales and Wade LeBlanc, Kikuchi simplified things in his delivery. He eliminated his double leg kick, sped up his tempo, and perhaps most importantly, relaxed a bit on the mound.

“I’ve been probably overthinking these last couple starts,” Kikuchi said through interpreter Justin Novak. “I feel like I’ve been tense since I came over here, so I went back and watched a lot of video, and today I really focused on relaxing and loosening up and just going out there and pitching.”

The Mariners got home runs from Kyle Seager, Austin Nola, Tom Murphy and Keon Broxton as they improved to 4-2 on their road trip and head to Tampa Bay with a 52-73 record, pushing a game ahead of the Blue Jays (52-75) by winning the series. Seager's big fly was his second in two days, and it extended his hit streak to 12 games.

The Mariners are heavily invested in Kikuchi, having signed him to a free-agent deal last winter that guarantees four years at $56 million and up to seven years and $109 million with potential options.

As one of the building blocks for their future push, Kikuchi needs to adapt to the Major League game and the different baseball used in the U.S. He appeared to take a needed step in that direction with Sunday’s showing while improving to 5-8 with a 5.19 ERA on the season.

“Yusei is a very talented pitcher, and we know that,” manager Scott Servais said. “He has the ability to have outings like this. There’ll be rough ones along the way, like anybody has, but I’m really happy and proud of him. It’s tough when you’re going through a season like this. He’s probably struggled more this year than in recent years, but he continues to try to learn from it and get better.”

After struggling with his mechanics in recent weeks, Kikuchi threw more freely on Sunday, with his fastball ticking up to 94-95 mph in the middle innings after sitting more in the 90-92 range in recent outings.

“To me, it all started with his fastball,” said Murphy, who caught Kikuchi for the eighth time this year. “He was consistently right at the top of the strike zone. To be able to command that pitch consistently, every hitter in here will tell you that you have to cover a lot of ground after that. For him to be able to do that as consistent as he was just set the tone for everything else he was doing.”

While the Mariners slugged four home runs in the sunny afternoon game at hitter-friendly Rogers Centre, Kikuchi kept the Blue Jays in the yard and issued just one walk with eight strikeouts.

Those were big improvements after allowing 23 homers, a .346 batting average and 28 walks in his previous 66 innings over 14 starts since May 25.

“I felt like I found something today,” Kikuchi said. “Tomorrow is another day, so I need to go out and make sure I don’t forget it and get back after it day after day and make sure I finish the season strong.”