As the roster is comprised now, the Nationals have a need to fill in the infield: Who is the team’s backup shortstop? Ian Desmond has played 442 of a possible 486 games there over the past three seasons, missing only four games in 2013. Late in the season, Manager Davey Johnson turned to Anthony Rendon to fill in at shortstop and he committed two errors and didn’t look completely comfortable. (See: the Aug. 22 game in Chicago against the Cubs.) Any major injury to Desmond would have perhaps forced the Nationals to call up struggling hitter Danny Espinosa from Class AAA Syracuse.

But what about next season? Rendon is a natural third baseman squeezed into the second base spot, and likely the leanding contender to earn the job after an open competition in spring training. Espinosa is a natural shortstop, who was also moved to second base, but his hitting woes have doomed him and he has much to prove. Steve Lombardozzi can play shortstop in a pinch, too, but his arm strength and range are better suited elsewhere around the diamond, such as his natural position of second base. Maybe the Nationals could seek a veteran free agent? Or with a strong showing in spring training, could Walters make a case to fill the role of backup shortstop?

Certainly. And Johnson indicated as much late last season. Walters, 24, is ready for the challenge and hopes to prepare his body with a vigorous offseason routine in order to compete for a spot on the roster next spring, his third in big league camp with the Nationals.

“Whatever they want to do, whether it’s left field, back-up catching, short, whatever, as long as I get to swing the bat,” Walters said during the final week of the season. “That’s the way I’ve been my whole life.”

Walters’ best season in the minors — a discovery of his power stroke, 29 home runs, a .803 OPS despite 134 strikeouts and a .253 average — earned him a September call-up to the Nationals. He saw brief action — 3 for 8 with an RBI and four games in the field, including a start a shortstop — and the Nationals are interested in seeing more. He is listed at 6-foot-2, 220 pounds and was rated as having the strong infield arm in the Nationals minor leagues. He has spent 347 games at shortstop in the minors, but can also play third base.

Walters still has obvious areas of improvement. He committed 31 errors in 104 games at shortstop this season and Syracuse Manager Tony Beasley, a former infielder, is constantly pushing Walters to do a better job of moving his feet while in the field. “He’s on me because he expects more,” Walters said of Beasley. At the plate, Walters entered the season with a conscious effort to improve his power stroke, and Beasley has also pushed Walters to cut down on his strikeouts and improve his plate discipline.

To continue working on areas of improvement, Walters is currently playing for the Bravos de Margarita in the Venezuelan winter league, along with outfielder Corey Brown and left-hander Danny Rosenbaum. Walters, however, will only play about five weeks, about half of the season. And he thinks that will help.

Last winter, Walters played an entire season of winter ball in Puerto Rico and then only had about a month to regroup before heading to Nationals spring training. “I didn’t come in as strong as I wanted to be,” he said. This winter will be different.

At the end of the season, Walters felt weaker and skinnier than he felt he should at just over 200 pounds. As a call-up with the Nationals, he had never played that deep into September. “I lose about 15 pounds during the season, so at the end, that 34-inch, 31.5-ounce bat feels like lead,” he said.

“That’s my biggest thing this offseason: coming in physically ready,” Walters added. “Getting bigger and stronger. Every time I see [Marlins’ Giancarlo] Stanton, I think, ‘Gosh dang, I’m doing something wrong.’ This year will be better because I’ll have more time before spring training.”

Walters, a Wyoming native whose family moved to Las Vegas when he was in high school, plans to load up on lean proteins and vegetables in the offseason and follow an intensive workout regime while at home. He will do everything from yoga to running to weight lifting to some circuit training exercises similar to the CrossFit routine. His target weight is 225 pounds. He hopes to be strong and impressive at the beginning (spring training) and near the end of the season (August).

“Every time August comes around, I feel more tired,” he said. “A little slower, a little more lethargic. I try doing everything I can and keep eating right. But I’m trying to push past that plateau. Maybe it was all that winter ball. But this year, yeah, just going after it.”

The goal is to obviously earn a spot on the Nationals’ major league roster.

“I’m not just competing for a job, I’m competing to be a starter,” Walters said. “I don’t say that negatively towards any guy we have. But I think if you’re not trying to do that or make a team, what are you doing? Getting a cup of coffee? I’m not satisfied.”