After the 500-foot bombs in high school, the major league hair-flips, the slow home run trots and the “Make Baseball Fun Again” hats, a significant moment is approaching Bryce Harper again, likely accompanied by a check of historic proportions.

The Nationals’ 25-year-old outfielder will, barring the unforeseen, become baseball’s highest paid player ever, likely drawing a contract worth close to half a billion dollars during the free agency season of 2019, and he will play wherever he wants.

Whatever deal he negotiates will usher in a new paradigm in sports business. And whatever that deal may be, he has declared he won’t speak of it until after the season, lest it somehow distract these Nationals from yet another season in which they are favorites to reach the postseason.

For good reason, then, comparisons to players before him in baseball’s modern era are scarce. Perhaps except for one:

“You know, just like Bryce, I was such a routine-oriented guy,” said Alex Rodriguez, who earned more than $440 million in his career. “I never wanted anything to take away from my preparation and my focus on the game.”

There are few athletes who could imagine what it feels like to be coveted as Harper, first as a high school phenom, then top choice in the 2010 MLB draft, now baseball’s next prime free agent.

But there is Rodriguez, who was recruited to play baseball and football at the University of Miami, was the top pick in the 1993 draft, and won three MVP awards in 22 seasons.

In 2007, his agent, Scott Boras (also Harper’s agent), announced Rodriguez would opt out of his contract with the Yankees the same night the Red Sox won the World Series. Hank Steinbrenner, son of then-owner George Steinbrenner, said there was “no chance” the team would re-sign A-Rod after Boras’s stunt.

The club ponied up $275 million over 10 years the next month to keep him.

And although Rodriguez’s advice to Harper is to stay focused on his 2018 season, to be the game’s best player is to command and manage that same attention.

“One constant,” Rodriguez said in a telephone interview, “whether you’re LeBron James or [Steph] Curry in basketball, or Tom Brady, when you’re the gold standard of the greatest baseball league in the world, the attention and the responsibility continues to shine on you.”

It’s like being the top quarterback on the high school team and every college is coming after you,” added Rodriguez, who will broadcast Sunday’s Nationals-Mets game as part of ESPN’s “Sunday Night Baseball” crew. “It’s going to be one team that’s happy and about a hundred that are disappointed, but that’s a great place to be.”

The front-runners for Harper’s services reportedly are big market ballclubs, such as the Yankees, whose ballpark is a haven for left-handed power hitters.

The Nationals, though, could remain an attractive option for Harper, Rodriguez said. A long-term deal with Washington could last Harper through the rest of his career, making him one of few players of his era to remain with a single franchise through their playing days.

“I always think that’s a great story for him, for the franchise, for baseball,” Rodriguez said. “I do know great things about the Washington National fans. They’re very knowledgeable, they’re very passionate and they’re hungry to win. And it’s been a great marriage for six years. That’s always my front-runner, and then from there it’s just a lottery.”

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