The first time Jake Rosenberg realized how much work he was about to do was during his first week in Israel, back in August. He’d just moved to Tel Aviv, a few months after visiting the country for the first time on Birthright.

Rosenberg, a Lower Merion native and Harriton High School grad, had signed on to play on the Israeli national baseball team in advance of the European Championships this summer, the precursor to the 2020 Olympics in Tokyo.

Until then, he was, for the first time in his life, a coach, working with a U16 and the U18 national team. As he walked onto a field for the first time last summer, he saw an Israeli player — 15 or 16 — having a catch with himself, throwing the ball against a wall and then running to pick it up as it dribbled away.

It was clear he wasn’t very good.

And yet, months later, the kid had learned how to become “somewhat of a good baseball player,” according to Rosenberg. Rosenberg and other coaches in the Tel Aviv region that he worked with — young Americans such as himself, or Israelis who’d been introduced to the sport long ago — had painstakingly worked with him and others like him for the whole year on the basics of throwing, hitting and fielding. Presto: His days of failing at baseball were over.

Small a gain as it may seem, teaching the fundamentals of the game to one interested Israeli at a time is how Israel will begin to build baseball competency across the whole country. For Rosenberg, it’s a chance to see the game he’s played at a high level his whole life in a totally different light. And, if he’s lucky, he could be a part of an Israeli baseball team seeking to shock the world like it’s 2017 all over again.

“Our team is very good,” Rosenberg said.

Rosenberg — son of Jewish Federation of Greater Philadelphia Chief Marketing Officer Steve Rosenberg, who also serves as the Exponent’s publisher’s representative — was a second team all-state player in Pennsylvania during his sophomore year, and spent the first two years of his collegiate career as an outfielder at Alvernia University. He transferred to Ithaca College, still playing outfield. After he graduated last spring, he went on Birthright, and had a wonderful time.

“I knew that I definitely wanted to come back,” he said. When his father apprised him of an opportunity to work with Israeli baseball players, Rosenberg jumped at the chance. “I was like, ‘Yeah, all right, I could do this for a year,’” he said.

Since August, Rosenberg has lived in Tel Aviv, working six days a week with area teams. Most of the players are Americans, or at least have one American parent; the full Israelis who play need a fair degree of coaching, he said. Still, his U16 team finished a better than expected 16th out of 20 in a tournament in Prague in the spring. And the U18 team he coaches will compete at the European Championship qualifier in Sweden starting July 8.

On July 1, he’ll begin playing with the national team at the European Championship qualifiers in Bulgaria; if they win the pool they’re placed in, they’ll have to beat the winner of another pool just to get to the European Championship. To get to the Olympics, all they have to do is win that pool. Almost none of the players know each other, and they haven’t practiced together yet. Easy enough, right?

“From the looks of it, we have a chance,” Rosenberg said.

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