J.D. Martinez didn’t just sit out on Friday night. He was also sitting on an 0-for-20 slump as he watched his team for nine innings.

In actuality, the key to Martinez’s day off was that he actually took it off.

On most days, whether he is playing or not, Martinez takes hundreds of swings and studies hours of video before the game even starts. This time, Martinez didn’t take one swing.

On Saturday, Martinez got up off the mat in a big way, most notably when he clocked a go-ahead three-run homer to right that lifted the Red Sox to a 5-3 victory over the Indians in 10 innings at Progressive Field.

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It was part of a three-hit game for Martinez, who teamed up with Kyle Schwarber (3-for-5, homer) to carry the Red Sox on a day when the rest of the offense didn’t do much of consequence.

Schwarber helped set Martinez up when he ripped a single to open the 10th, pushing automatic runner Jarren Duran to third.

For his game-turning hit, Martinez got ahead in the count 2-1 and mauled a meaty cutter by Indians reliever Nick Wittgren for his 24th homer of the season, a 106.2-mph drive to right that traveled a Statcast-projected 395 feet.

“I went up there, chased the first pitch, and then I told myself to just relax and do what I always do and look for the ball up, and just try to put the ball up in the air and try to get the run in, really,” said Martinez. “I was just fortunate enough to flush it and get it out.”

The hit provided a big lift for the Red Sox, who have now won five of their last six to come out of their recent funk. By taking the first two games in Cleveland, Boston has now won three series in a row. Before that, the Sox had lost five of six series.

If Saturday can serve as a springboard for Martinez, things will suddenly become much easier for the Sox, particularly with the addition of Schwarber, who has been red-hot since he came off the injured list.

“The offense, we’ve been kind of off, on, off, on,” said Martinez. “We were able to put some runs up today. If I get hot, it would be nice for us going into this last month of the season. It would definitely help us.”

With a 75-56 mark, the Sox trail the Yankees by two games for the top Wild Card spot, but lead the A’s by 3 1/2 games for the second spot.

The stretch run figures to be exciting, and there likely aren’t many more days off in Martinez’s future. But this one clearly did the trick.

“Definitely. I don’t get too many off-days, and I’m good with that,” said Martinez. “I love being out there, I love grinding it out. So just being able to step away and just kind of relax, I took my mind off everything, and it gives my body a rest because, you know, I'm all day just swinging, swinging, swinging.

“The four at-bats you see, those are just four swings I take during the game, but the ones outside of the game catch up to me. So just being able to take something off and going out there watching the guys play and rooting them on, it definitely helps me.”

Making Martinez’s day off on Friday even better was when unlikely hero Jonathan Araúz roped a three-run homer in the top of the eighth that led the Sox to a comeback win. Only after the game did Martinez allow himself to do just a little bit of mental preparation.

“I studied at night when I got [to the hotel], and I was studying what I wanted to work on and stuff like that, but no, I was just trying to get away from everything,” Martinez said. “Just be a cheerleader.”

Red Sox manager Alex Cora also deserves credit for resisting the temptation to use Martinez as a pinch-hitter, even as Friday’s game seemed to be slipping away.

It would have been easy for Cora to give in, considering the Red Sox lost Kiké Hernández and Christian Arroyo on short notice to the COVID-19 injured list prior to Friday’s game.

“We had a lot of stuff going on, but I was like, ‘No, he’s not playing,’” Cora said. “It’s not worth it because if he plays yesterday, then probably today it doesn’t happen, and we’ve got to be very careful with these players. I know a lot of people get on me because of the rest and all that stuff. For us to be where we want to be, and [what] we’re trying to accomplish, we have to make sure these guys are close to 100 percent, which is almost impossible.”

What would be truly impossible would be for the Red Sox to realize their loftiest goals this season if Martinez isn’t a big part of what they are doing.

“Yeah, I mean, [Martinez] is a huge stud at the plate,” said Nathan Eovaldi, who had another solid start. “He’s been scuffling a little bit, but you get him back swinging like we all know he can, like he was at the beginning of the season, we’re going to be even more deadly out there.”