VIERA, Fla. — Nationals outfielder Bryce Harper has never faced a pitcher younger than him in his entire professional career. Not in the minors when he was on the way up as a wunderkind prospect, not in any of his three Major League seasons, and not even in rehab trips to Potomac at the Class A Advanced level in 2013 and 2014.

It may feel like Bryce Harper has been a famous baseball player forever, but Harper only turned 22 in October and was the youngest National League player to appear in at least 100 games in 2014. Though some fans, somehow, have deemed Harper a bust due to the enormous hype that preceded his big-league debut and even called for his demotion when he struggled last summer, he has among the brightest futures of anyone in the game even if he never improves upon his first three seasons.

About that: Position players are generally expected to peak in their late 20s and begin declining in their early 30s. Harper amassed 8.6 wins above replacement (WAR) over his 2012 and 2013 seasons, at ages 19 and 20. That’s real good for any age. If he could merely replicate that production every year until he’s 32, he’d finish his career with a borderline Hall of Fame case.

“I’m just trying to go in there, stay healthy and be on the field, and play the way I need to play,” Harper said. “And if that’s what I’m doing, then hopefully our team’s winning and doing the things we need to do to get to that next level.”

Harper endured the worst of his three big-league seasons in 2014, missing 57 games with a thumb injury he suffered sliding headfirst into third base on a triple in late April. Hand injuries are known to sap power, and Harper mustered only five extra-base hits in his first 100 at-bats after returning. But he heated up in August and September to help his Nats cruise to the postseason.

Harper also missed time in 2013 after a head-first collision with the outfield wall, a scary moment that embodied both his hyper-energetic style of play and his apparent lack of any instinct for self-preservation. Now, Harper says he recognizes the need to occasionally temper his aggression to stay on the field.

“It’s about picking my spots,” he said. “I’m still playing hard, but if we’re up 7-0 or we’re ahead in a game that looks like a blowout kind of piece, then I’ve just got to be a little bit smarter.”

Many of baseball’s readily available projection systems seem optimistic on Harper, even coming off his injury-riddled year. Steamer puts Harper at a .276/.359/.484 line for 2015, and ZiPS expects .280/.364/.494. Harper himself declared that “the sky’s the limit” in late February.

“I think he’s focused,” said manager Matt Williams. “I think he’s prepared. I think he came here in great shape. We forget that last spring he was coming off knee surgery, so he was really slow getting going in that regard. That’s never easy.”

One added wrinkle that should up Harper’s already sky-high entertainment value in 2015 is a move to playing right field on a full-time basis after playing mostly left in 2013 and 2014. The position will likely give Harper more opportunities to show off his throwing arm, as he did Saturday in an exhibition against the Cardinals, when he delighted the crowd with a perfect strike to third base in an effort to catch an advancing runner.

“Early in the spring, you don’t want to go too full bore,” he said. “But adrenaline kicks in, and it’s a fun opportunity to be able to let it air out a little bit.”

Though Harper still has plenty of time to improve, and though those projected lines are excellent for any player at any age by today’s diminished offensive standards, it might take more to shake the nagging insistence from some corners that he isn’t as good as once advertised. Part of the issue, almost certainly, stems from Harper having entered the Majors at around the same time and around the same age as Mike Trout, who has been considerably better over their first few years.

But that’s not Harper’s fault: Literally no one has ever been as good as Mike Trout was over his first few years.