Dave Martinez was standing on the top steps of the Washington Nationals’ dugout, as he always does, carefully watching pitcher Aníbal Sánchez’s mechanics during the fifth inning Sept. 15. Everything was normal. Then his chest began to tighten.

It was a sharp pain — “Heartburn but way worse” is how Martinez described it — and the 55-year-old manager was confused. He immediately ran calculations in his head: I’m healthy. I work out every day. I try to eat well, though I do like steak. This can’t be a heart attack.

He figured it was just a chest cramp. He tried to stretch it out, moving his right elbow like a windmill, but soon lost feeling in the arm. Then his left thigh felt numb and he couldn’t catch his breath. He called for Paul Lessard, the team’s head athletic trainer, and it was decided that Martinez needed to go to the hospital. Immediately.

“I was so, so scared,” Martinez said in an interview Saturday, offering his most detailed public account to date of the incident two weeks ago. Sitting cross-legged on a couch in his office, shaking a cold that felt trivial after what he had experienced, Martinez revealed the episode was far more alarming than previously known. There were tears in his eyes. “I started thinking about my kids, my family, my players, this team,” he said. “And then I thought, ‘Man, I am going to let so many people down.’ If I can’t do this, then what happens?”

It happened on a Sunday. On Monday, when the team traveled to St. Louis, Martinez stayed in Washington and underwent a cardiac catheterization. The results were clean, and it was determined that the scare was exactly that. General Manager Mike Rizzo told reporters that Martinez was resting, had arrived home and could rejoin the team when cleared to fly. The tests were publicly painted as a precaution. The whole episode was barely discussed once Martinez returned in Miami after three days away.

But Martinez was shaken, and he often thinks about Sept. 15 as Washington prepares to face the Milwaukee Brewers in the National League wild-card game Tuesday night. He declined to provide further details in his first meeting with reporters at Marlins Park. He didn’t mention then that he flew to Miami before doctors had cleared him to do so, because he couldn’t stand watching games on TV and he felt up to being on a plane for a couple of hours.

And he quietly told a few players, “I really dodged a bullet.” He told Max Scherzer, his ace and one of the club’s leaders, “It was a lot more than just a little scare.” He found an even bigger appreciation for showing up to the ballpark every day.

“I’ve been around baseball for a really long time,” said Martinez, who began his playing career with the Chicago Cubs in 1986. “I didn’t know I could want to be here any more than I do, have any more love or passion for this. But being away, even for just a week, that was the worst. I didn’t know what was going on. I never want to do that again.”

Martinez’s mind began to wander when he was in the back of an ambulance that afternoon, strapped to a gurney, tubes attached to his body to provide fluids. The chest pains were subsiding, and he regained feeling in his arm and leg. He is a father of four, three sons and a daughter, and a grandparent. And he is a manager to dozens of players, even more than 25 in September, and didn’t want them to lose him at such a critical point of the pennant race.

That’s what he considered on the way to the hospital. He also kept wondering what caused the chest pains in the first place. It had been a stressful weekend at Nationals Park, particularly the night before he had to leave in the sixth inning. Fernando Rodney hit Charlie Culberson in the face with a fastball. While Culberson was on the ground bleeding and in considerable pain, the umpires checked if he had swung on the pitch. Martinez got ripped in articles and on social media for being insensitive. He emotionally defended himself, that night and the next morning, before later realizing that it could have contributed to what happened in the dugout.

“I asked myself, ‘Is this game really stressing me out that much?’ ” Martinez recalled. “We had been in really tight games and the race, what happened with Culberson was unfortunate, and I just worried that it had maybe become too much. I requested that they do a stress test just to see. It seemed to make the most sense.”

The stress test didn’t reveal any issues. He remembered the doctors telling him, “You’re about as calm and normal as anybody we’ve seen.” They instead changed Martinez’s diet, told him to stop consuming caffeine — he was up to five or six cups of coffee a day — and quit drinking alcohol for the time being. He’s been instructed to stand less during games and has mostly listened. Lessard is keeping a close eye on him. Everyone is, so much so that Martinez joked in Miami that he’d have to save a new bottle of wine until the winter holidays.

Once the team returned from that Miami trip Sept. 23, at the start of its final homestand, Martinez went back to the hospital for a scheduled round of follow-up tests. The results were good. He will have routine check-ins with a cardiologist in the coming months. After this one, in the afternoon before a night game against the Philadelphia Phillies, the doctor suggested he go home and rest. Martinez smiled.

Then he went straight to the ballpark.

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