Jimmy Cordero, one of the Nationals' latest cuts, was optioned to Class AAA Fresno. (Toni L. Sandys/The Washington Post)

WEST PALM BEACH, Fla. — The Washington Nationals have 10 days to set their 25-man roster for Opening Day on March 28, and they got closer to that when they made their third round of spring training cuts Monday.

The Nationals optioned Austin Voth, Kyle McGowin, Tanner Rainey and Jimmy Cordero, all right-handed pitchers, to Class AAA Fresno. They also reassigned outfielder Hunter Jones and right-handed reliever J.J. Hoover to minor league camp. Voth, McGowin, Rainey and Cordero were sent to Fresno because they are on Washington’s 40-man roster. Jones and Hoover, nonroster invitees to spring training, will get their assignments in the near future.

Manager Dave Martinez made the cuts, which trimmed the roster to 40 players, after a pair of split-squad games Monday. The Nationals lost, 7-1, to the Miami Marlins in West Palm Beach; they won, 6-5, over the New York Mets in Port St. Lucie.

Among the players cut, Cordero has the most experience with the Nationals. The 27-year-old reliever debuted in August and finished with a 5.68 ERA in 19 innings across 22 appearances. He could not take the next step this spring, giving up 12 hits and five runs in five innings.

Rainey came to the Nationals in the December trade that sent starter Tanner Roark to the Cincinnati Reds. The 26-year-old had a 24.43 ERA in seven innings for the Reds in 2018 as he struggled with his command, compiling a high strikeout rate and high walk rate. His fastball is in the mid- to high-90s, and he has a solid slider — promising stuff for a late-game reliever.

Voth and McGowin are depth starters, probably the Nationals’ eighth and ninth options behind Erick Fedde and Joe Ross, who will back up a strong rotation of Max Scherzer, Stephen Strasburg, Patrick Corbin, Anibal Sanchez and Jeremy Hellickson. Nine Nationals pitchers made three or more starts last season — including Ross and Fedde — which is why Martinez wants to stretch out Voth and McGowin going into the season. Each made his debut and first major league start in 2018.

Hoover is a 31-year-old reliever who has played seven seasons in the major leagues, spending his first five years with the Reds, one with the Arizona Diamondbacks and parts of last year with the Milwaukee Brewers. He signed a minor league contract with the Nationals last month and impressed Martinez in the past five weeks.

“Hoover’s been good; he got better as spring training went along,” Martinez said Monday. “It’s nice that he’s going to be around for some depth, and you know how this goes. We’re going to need more than seven, eight pitchers this year in the bullpen. I liked what I saw — I really did.”

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