ST. PETERSBURG — Yandy Diaz tried to make the most of his “day off.” The Rays first baseman had a rare chance to get off his feet, so he hung back and watched the first few innings of Saturday’s game from the clubhouse, resting.

In the top of the seventh inning, however, his respite was over. A call came from the dugout, and Diaz had to put on his batting gloves and his cape, and go out and save his team.

He hit a go-ahead, pinch-hit double in the bottom of the seventh and then a walkoff, two-run home run in the ninth as the Rays rallied for a 7-5 win over the Mariners in front of 18,008 at Tropicana Field.

“I am one of those guys who doesn’t really like to come in late in the game,” Diaz said via team interpreter Manny Navarro. “I like a day off when I have the day off, but you’ve got to know being on this team, you’ve got to be ready at any moment. I am just happy I could help the team.”

It was the ninth walkoff win for the Rays (87-56), third-most in the majors, and 33rd time they have come from behind to win. They improved to a season-high 31 games over .500 and 9-5 when tied after eight innings, including five of the last six times they found themselves tied that late.

“I think it’s honestly just the game plays out that way and gives us those opportunities,” said shortstop Taylor Walls. “Second off, everybody’s pretty composed. I feel like we’re pretty comfortable in those situations. We don’t let the moment get too big. We take a pitch-by-pitch, next-man-up mentality and we just try to do our best to grind it out and not be the last one at the plate.”

Walls singled in the tying run in the seventh and scored on Diaz’s pinch-hit double, giving the Rays a 5-4 lead. After the Mariners tied it in the eighth, Walls worked a two-out walk to give Diaz another chance.

“I was looking for a good pitch to hit there,” Diaz said. “Luckily, I was able to get it and I was able to connect on a good ball.”

It was the Rays’ major league-leading fifth walkoff home run but just Diaz’s second walkoff plate appearance and first career walkoff home run.

Still, it didn’t surprise anyone with the Rays. In the seventh inning or later, Diaz is tied with the Rangers’ Corey Seager for the highest batting average in the majors at .371.

“You have so much trust and confidence in him that he’s going to give you a really good at-bat,” Rays manager Kevin Cash said. “He’s not always going to go up there and get a hit, square it up, but he’s going to handle good pitching. He’s going to handle breaking balls.

“And he did that. He laid off a tight pitch inside and expanded on the slider first at-bat, then I’m not sure what he hit, was an off-speed pitch or not, for the double. And then the last at-bat, probably want him up as much as anybody.”

The Rays found themselves in an early 3-0 hole.

Aaron Civale survived a 36-pitch first inning after he walked two batters — one bringing in a run — and hit another. He allowed four runs, including a Julio Rodriguez solo home run, on four hits over five innings. He walked three and struck out three. It was the fifth time in seven starts with the Rays that he went five innings or less.

Third baseman Isaac Paredes, who left with a contusion on his right hand after getting hit by a pitch in the fourth inning, doubled in a run in the first, trimming the Rays’ deficit to 3-1.

After Roriguez homered in the second, Walls (1-for-2 with two walks and three runs scored) drew a two-out walk in the fifth and scored on Brandon Lowe’s two-run double, narrowing Seattle’s lead to 4-3. Walls’ RBI single in the seventh tied the game at 4, and Diaz’s run-scoring double put Tampa Bay ahead 5-4.

Osleivis Basabe’s fielding error with two outs in the eighth allowed Eugenio Suarez to reach base. Sam Haggerty’s single to right put him on third. He scored on Robert Stephenson’s wild pitch, tying the game at 5.

But Diaz was not worried.

“We say the game isn’t over until that 27th out is made,” he said with a shrug. “And for us, we went out there to try and battle and we never gave up until the end.”

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