Bryce Harper was 15 years old when he was first on the cover of Sports Illustrated, and after winning an MVP award for what he accomplished in his age-22 season in 2015, he wore a tux for the front of ESPN The Magazine. For that story, he told our Tim Keown, with his typical bluntness, "I will never say anybody's better than me. I don't think those words will ever come out of my mouth."

Nobody in baseball history has gotten more exposure at a younger age than Harper, and he mostly has handled the attention and scrutiny in the same manner he attacks a belt-high fastball: Bring it on.

But because of his early fame, Harper has had to learn and grow in years in which a lot of peers would be fretting over the choice of colleges and a major, and how to write a proper resume. Because of his skill as a baseball player, he doesn’t have to worry about how long he can stay covered under his parents’ car insurance. Harper has other, different challenges -- like how to create some personal space while living under the watchful eyes of 40,000 fans daily.

Some teammates noted last year that Harper spent more time in the clubhouse, and wondered if it increasingly became a haven for him -- a place where he could go about his day most comfortably, without having to worry about being the caged creature in the zoo.

The timing of his $21.625 million extension for the 2018 season with the Washington Nationals, which was announced Saturday, is interesting and perhaps a sign that Harper isn’t necessarily devoted to the idea of chasing the biggest deal from the biggest bidder through free agency. And look, the Phillies probably would love to have him. He would be perfect for the Yankees -- and for Yankee Stadium, with its short right-field porch.

If Harper goes to New York, he probably could be a bigger star than he would be if he stayed in Washington, just as Reggie Jackson was, when he signed with the Yankees. But Harper also would have to reprove himself all over again, facing much higher expectations from a Yankees fan base that would turn on him if he generated anything less than an MVP-caliber performance -- and that might not even be good enough, if championships didn’t accompany his numbers.

In the end, maybe he’ll want that. Maybe he’ll be drawn to that pressure, that challenge.

But like everybody else his age, Harper might be trying to figure out what makes him the happiest. He knows this: No matter where he lands, he will make plenty of money. The Nationals will be willing to give him a record-setting deal. But he should weigh the relationships he has built in Washington, the safe zone. He has a strong relationship with GM Mike Rizzo, who is, like Harper, under contract through 2018. He’s beloved by Nationals fans.

Harper should call Cal Ripken and ask what it meant to him to stay in Baltimore for his whole career -- perhaps for a little less money than he might have made if he had chased every nickel in free agency. Harper should call Derek Jeter and ask why Jeter never bothered testing the market when he became a free agent late in his career, even when Yankees GM Brian Cashman advised him to do so in the middle of a tough negotiation.

Jeter had a home with the Yankees, and Harper has a good thing in Washington. Whether he wants something different is something he’ll have to decide.

But maybe he should draw upon the lesson of Alex Rodriguez, who became a free agent in the winter of 2000 under the same circumstances as Harper will be: He was in his mid-20s, regarded as one of the sport’s best players, a major star. The Mariners wanted to bestow a unique deal on Rodriguez, for $90 million over three years. But Rodriguez left Seattle to sign a 10-year, $252 million contract with the Rangers. Within weeks after that deal was consummated, Rodriguez was quoted as saying that all things being equal, he would have loved to have signed with the Mets.

Rodriguez could have played anywhere he wanted -- for varying degrees of money, of course -- and he went to a place where he didn’t necessarily want to be. Three winters later, he and the Rangers divorced, and he was traded to the Yankees. Through circumstances, he never really forged the same kind of legacy he might have had with the Mariners.

The leap to New York worked out for Reggie Jackson, because of the Yankees' 1977 and 1978 World Series triumphs. It didn’t really work out for Rodriguez, largely because of his two rounds of PED admissions and his yearlong suspension.

Harper can’t know what his New York or Philadelphia experience would be like unless he leaves. What he should know is that he has more peace in Washington than he would have anyplace else.

Harper has always chased challenges on the horizon. He played against older competition while he was still going through puberty, got his high school degree so he could enroll in college sooner than his peers, and slugged his first homer in the big leagues at 19. If Harper follows that habit, formed at an early age, then of course he will become a free agent, to pursue bigger (fame) and more (money). Which would be his right.

But through accumulated wisdom, maybe Bryce Harper is already learning that bigger and more isn’t always better.