“He’s a 20-year-old kid, he’s got great energy and great stamina and strength, so I’m not worried about tiring him out at 20 years old just from playing in center field,” Nationals GM Mike Rizzo said of Bryce Harper. (Jonathan Newton/The Washington Post)

General Manager Mike Rizzo departed the GM meetings on Friday afternoon with the theme of the Washington Nationals’ offseason very much in place. And, like most everything about the franchise’s future plans, the ability of Bryce Harper served as a central factor.

After he laid groundwork and met with other teams and agents, Rizzo believes the Nationals possess numerous options and multiple, layered ways in which to shape their 2013 roster. The Nationals have those choices at their disposal in part because of Harper, who can toggle around the outfield based on the Nationals’ needs.

Harper could stick in center field or move to left, which allows the Nationals contingencies in case free agent first baseman Adam LaRoche signs with another team and Michael Morse moves from left to first base. Harper played center field for the first time and excelled — advanced defensive metrics rated him as one of the best defenders in the league. If he played left, Harper would have one of the best arms at his position in the majors.

But Harper’s versatility also raises another question: How long can he play center field? The Nationals were wary last season when they moved him there, worried about the strain it would place on his body compared with other positions. Harper, about 6 feet 3 and 220 pounds, is already a large man, and he will keep growing. They know, eventually, they will need to keep him in the corner outfield to save his body from constant pounding.

“The word ‘eventually’ is key there,” Rizzo said. “He’s a 20-year-old kid, he’s got great energy and great stamina and strength, so I’m not worried about tiring him out at 20 years old just from playing in center field. He’s going to play every day somewhere, and he’s going to play at 110 miles an hour wherever he’s at.”

As last year wore on, Rizzo and Manager Davey Johnson saw Harper become a more graceful runner, with easier strides that taxed his body less. But they still believe it will be unsustainable to keep him in center, tracking down more balls than he would in a corner spot. His agent, Scott Boras, believes “eventually” is sooner than later.

“When their weight gets above 225 to 240 [pounds], and these guys can leap so high because they’re so athletic . . . the stress on their joints and ligaments is immense,” Boras said. “Particularly when they’re middle-of-the-lineup hitters, each team has to balance that risk factor. In the end, those types of players usually end up being corner outfielders because they’re so valuable offensively. You don’t want to risk too much on the requirements and burdens of center field on those types of athletes.”

For now, the Nationals still consider Harper an option in center field for the 2013 season. And that multiplies the ways they can plan. They could simply re-sign LaRoche and play with essentially the same lineup as last season. But the longer LaRoche tests the market, the longer he has to find an offer the Nationals wouldn’t match.

On Friday, LaRoche declined the Nationals’ one-year qualifying offer, ensuring the Nationals an extra draft pick if he signs with another team. LaRoche will be in demand on a market bereft of quality first basemen; the Boston Red Sox have already shown strong interest.

The Nationals like LaRoche, especially the way his demeanor fits into their clubhouse and his left-handed bat fits into their lineup. They would like to re-sign him, but perhaps not for a commitment of longer than two or three years, in part to keep open the possibility of moving Ryan Zimmerman from third to first in a future season. More immediately, the Nationals are not locked into any one plan.

“I don’t have a distinct number one priority,” Rizzo said Friday. “We’ll see what’s the best deal, and then we’ll make our decisions off that. We’re very versatile in that regard. If we get a pitcher, then the other dominoes fall. If [Adam] LaRoche signs, then the other dominoes fall.

“We’ve kind of got multiple things going on. We’ll see what falls first, and then we’ll take our preferential list after that. We’ve got parallel plans going. We’ve got parallel discussions going.”

If LaRoche leaves, the Nationals could acquire their outfielder in free agency, with center fielders Michael Bourn and B.J. Upton being likely targets. The Nationals consider both excellent defensive players, and they derive offensive value in far different ways. Bourn is an on-base spark plug, while Upton, who at 28 is a year and a half younger, collects strikeouts in bushels, but also whacked 28 homers in 2012.

The best player apparently available in a trade is Justin Upton of the Arizona Diamondbacks, whom Rizzo drafted No. 1 overall when he was their scouting director in 2005. Justin Upton, B.J.’s brother, plays right field and therefore would be an option that would require keeping Harper in center. Justin Upton had a relative down year in 2012 as he played through a thumb injury, but he is only 25 and finished fourth in the 2011 NL MVP voting.

“He’s a great player,” Rizzo said. “All the trades, you have to balance. Of course Justin Upton improves our club. He improves any club. But what holes does it create to get him? Do the holes create more problems than the acquisition?”

When the Nationals consider trades this winter, Rizzo said, they would attempt to deal from the positions of depth. The Nationals consider pitching and infield to be their two deepest spots, from top to bottom, the major leagues down to the lowest minor league rungs.

They believe they have an abundance in both spots. And this winter, with all their different choices and the variance of their plans, abundance is something the Nationals know well.