There had never been a day like this in Major League Baseball.

Japanese-born starters had faced each other 11 times in the majors, dating to 1999, but never before had Japanese-born former teammates from Nippon Professional Baseball squared off as starting pitchers in an MLB game.

This time it was 27-year-old righthander Masahiro Tanaka for the Yankees and 35-year-old righty Hisashi Iwakuma for the Mariners on Sunday at Yankee Stadium. They were on the same side with the Tohoku Rakuten Golden Eagles from 2007-11.

NHK beamed this reunion game back to Japan, a national telecast for the bleary-eyed. First pitch: 1:09 p.m. here, 2:09 a.m. there. Those who were wide awake here and those who managed to stay awake there saw Tanaka outpitch Iwakuma as the Yankees edged Seattle, 4-3, to end a four-game slide.

“Just extremely satisfied being able to get that win,” Tanaka said via an interpreter. “Obviously, facing against a former teammate was one thing, but another thing was I was able to help stop the four-game skid. So in that sense, I think today was a good day.”

Tanaka allowed two runs in each of his first two outings and received no-decisions after going only 5 2⁄3 and five innings, respectively. But he was sharper and threw harder in this third start, topping out at 94.5 mph and going seven innings, a season best for the staff. Tanaka allowed three runs (two earned) and six hits. He struck out six and walked none during his 93-pitch afternoon.

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“The [better] weather, that does play a little bit, but I think we’re getting a little bit deeper into the season,” Tanaka said. “So I think the [arm] strength is sort of coming together, starting to build up.”

Like Tanaka, Iwakuma worked seven, yielding four runs and eight hits. Iwakuma gave up the go-ahead run in the fifth on a wild pitch and fell to 0-2.

“I was very excited to face . . . your ex-teammate,” Iwakuma said, also via an interpreter. “Just watching him, in general, he was pitching with composure and kept the ball down. Looking at that, I said to myself, ‘I’ve got to keep the ball down, too.’ ”

The Mariners could have done considerable damage against Tanaka right off the bat. With one down in the first, Seth Smith grounded a single into center, Robinson Cano reached on an infield hit and Nelson Cruz sliced a single into right, loading the bases. But Tanaka picked up a run-scoring forceout and a strikeout.

“I thought his stuff was really good today,” Joe Girardi said. “It’s the best game he’s pitched all season.”