FORT MYERS, Fla. — The Red Sox big league pitching staff has been consistently strong through the first week of spring training, but Wednesday a couple of arms finally ran into trouble during the club’s 4-3 loss to the Washington Nationals.

Zack Kelly and Jorge Benitez, both contenders for a big league bullpen spot, each got roughed up in their respective inning of work. Kelly gave up two runs on three hits and two walks during the third inning, allowing the Nationals to tie the score at 2-2, and Benitez also gave up two runs on three hits and two walks while recording only two outs in the fifth, during which Washington took the lead for good.

Josh Winckowski made his first start of the spring and performed well, throwing two scoreless innings while allowing no hits and a walk with one strikeout, and relievers Greg Weissert, Cam Booser, Luis Guerrero and Theo Denlinger all threw one scoreless inning each.

Rafaela keeps rolling

Center fielder Ceddanne Rafaela has gotten off to a strong start this spring, and on Wednesday he went 1 for 2 with an RBI single in the top of the second inning. That followed an RBI knock by catcher Mark Kolozsvary (2 for 3, 2 RBI) and improved Rafaela to .333 with a .914 OPS on the spring.

Kolozsvary’s second RBI single came in the top of the sixth and cut the Red Sox deficit to 4-3, but that’s as close as Boston got.

Utility player Pablo Reyes got the start at first base, his latest opportunity to show he can be a viable backup at the position, and went 0 for 1 with a walk. Presumptive backup first baseman Bobby Dalbec (0 for 2, 1 walk) started at third, and right fielder Wilyer Abreu’s tough start to the spring continued with an 0 for 3 day with three strikeouts.

Though it’s a tiny sample size, the rookie outfielder is now 0 for 10 with six strikeouts and two walks through his first four games. Abreu still projects as the likely starting right fielder on Opening Day, but the club no doubt hopes to see his bat heat up soon.

Casas back, Wong bruises knuckle

Triston Casas was back in the Red Sox clubhouse Wednesday after being away with the flu for the first half of the week. He’s expected to focus on workouts over the next day or so before getting back in the Red Sox lineup at some point in the near future.

Connor Wong (elbow soreness) is progressing towards a return behind the plate, though on Tuesday he got dinged up during live batting practice when his hand accidentally got hit by a bat following a swing. Wong said he’s got a bruised knuckle but that it’s nothing to worry about and it shouldn’t affect his return timeline. The next step will be throwing to second base — he threw to first and third on Tuesday after getting hit — and the expectation is he isn’t far away from getting back into a game.

Who’s up next?

Garrett Whitlock will make his second start of the spring on Thursday at home against the Detroit Tigers, and he’ll be followed out of the bullpen by Cooper Criswell, Lucas Luetge, Chase Shugart and Andrew Politi. The expectation is most of Boston’s big league regulars will be in the lineup as well, and first pitch is scheduled for 1:05 p.m.