Victor Robles will compete with Michael A. Taylor to be the Nationals' starting center fielder. (Katherine Frey/The Washington Post)

Spring training begins for the Washington Nationals in West Palm Beach, Fla., this week, and the team has a long to-do list to work through before Opening Day.

Players need to get back into the groove after a long winter. A handful of new faces need to get acclimated to the organization. Manager Dave Martinez and his coaching staff are promising to take a new, fundamentals-driven approach, and returning players will need to adjust.

But, above all else, the Nationals need to chisel a field full of players into a 25-man roster for their season opener against the New York Mets on March 28. That will include a few different competitions throughout spring training, namely for the team’s fifth starter, final bullpen spots and everyday center fielder. Here is how those battles look heading into the first pitchers and catchers workout Thursday.

Fifth starter

This once promised to be a one-on-one matchup between Joe Ross and Erick Fedde, but then the Nationals signed veteran Jeremy Hellickson to a one-year deal and made him the front-runner. Hellickson, who is 31 and will make a $1.3 million base salary with the potential for an additional $4 million in incentives this season, made 19 starts for Washington in 2018 and finished with a 3.45 ERA. He was mostly a two-times-through-the-order pitcher, only twice finishing the sixth inning, but could give the Nationals a dash of reliability in a rotation that already includes Max Scherzer, Stephen Strasburg, Patrick Corbin and Anibal Sanchez.

With Ross and Fedde, the Nationals have two potential back-of-the-rotation starters who could benefit from controlled opportunities with the Class AAA Fresno Grizzlies. They could throw as many pitches or innings as the Nationals want them to, which is important for two players coming off recent injuries. Ross missed almost all of last season while recovering from Tommy John surgery he underwent in 2017, and Fedde was out for most of last summer with right shoulder inflammation. Ross made three starts after returning, and Fedde, when healthy, had trouble staying effective past the fourth inning. Each is expected to have a chance against Hellickson, even if he has the inside track.

The competition also includes Henderson Alvarez. Alvarez has not pitched a full season since 2014, when he was an all-star with the Miami Marlins, and has since been hampered by repeated injuries. He signed a minor league deal early in the offseason and will most likely serve as a depth starter if he remains healthy. But he also has a shot, however long, to impress the Nationals in spring training.

Final bullpen spots

If the Nationals plan to carry seven relievers into Opening Day, a safe assumption based on most of last season and their expected roster construction, there seem to be five players locked into the bullpen: closer Sean Doolittle, Trevor Rosenthal, Matt Grace, Koda Glover and Kyle Barraclough. After that, the final spots could go to any of Sammy Solis, Wander Suero, Justin Miller or Vidal Nuno, who was signed to a minor league contract in January that included an invite to spring training. And if Hellickson is beat out by Ross or Fedde for the fifth spot in the rotation, he will likely join the bullpen as a long man, making for one fewer available spot.

Of Solis, Suero, Miller and Nuno, it looks as if Suero has a very good shot to earn one of the two potential openings. Suero, a 27-year-old righty, impressed the Nationals after debuting last season and his splits against left-handed hitters — a .237 average and .707 OPS against in 87 plate appearances — make him particularly exciting.

Solis would give the team another needed left-handed option after closer Doolittle and the versatile Grace, but he has a lot to prove in spring training after a dismal 2018.

Miller, who revived his career with the Nationals last season, could plug into a variety of roles and moonlight as a long reliever if Hellickson is kept on a short leash. Nuno, who is 33 and had a 1.64 ERA in 33 innings with the Tampa Bay Rays last season, is similar to Miller in that he could carry out a few duties while also giving the Nationals another left-handed option to go with Grace and Doolittle.

Center field

It is hard to tell if there is a true position battle in center field, or if the Nationals are looking to motivate Michael A. Taylor after a lackluster finish to 2018. Victor Robles, 21, has been one of the Nationals’ top prospects for a few years now and, though he has just two months of major league service time, he seems ready to take on a bigger role playing between left fielder Juan Soto and right fielder Adam Eaton. Robles has the rare potential to be a five-tool player, and in his limited opportunities last September he flashed an ability to change games with his speed and arm strength.

But the Nationals maintain that Taylor, 27, will get a fair shot to be the Opening Day center fielder. Taylor was an everyday player for much of 2017 and finished that season with a .271 batting average and 19 home runs. He could not carry his success into 2018, batting just .122 in August and .200 in September. It was difficult for Taylor to find a rhythm at the plate toward the end of the year with Robles’s September arrival turning him into a pinch-hitter and late-game defensive replacement. He has a lot to prove in the coming weeks as Washington gives him an opportunity against one of its potential young stars. And even if Robles does win the spot, it is likely the Nationals regularly mix in Taylor so Robles isn’t burdened by such a heavy and unfamiliar workload.

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