WASHINGTON -- Of all the trends of this Yankees season, two of the more problematic continued in tandem on Wednesday night at Nationals Park.

What is it about southpaws?

Left-handed pitching has been an Achilles’ heel for the Yankees’ offense all season. And for one of their key left-handed starters, Carlos Rodón, the first inning has been a particular bugaboo.

Both came to a head Wednesday, contributing to the team’s 5-2 loss to the Nationals. Rodón endured an erratic first inning, and the Yankees’ offense was unable to figure out left-hander MacKenzie Gore as New York -- which faced three left-handed starters this week -- dropped two of three in the nation’s capital.

While the Yankees lost, so did the Orioles later on to the Dodgers, so New York's lead atop the American League East remained at one game.

“We’ve got to keep creating as many opportunities as possible,” manager Aaron Boone said. “But we didn’t do enough the last two nights pushing runs across.”

Rodón has MLB’s fourth-worst ERA in the first inning (minimum 20 starts) this season, and he ran into immediate trouble Wednesday when top Nationals prospect Dylan Crews pulled Rodón’s second pitch out to left-center field for his first career homer. Crews’ leadoff tater was the ninth allowed by Rodón in the first inning this season, tied for the second most in MLB.

Rodón allowed a single to No. 2 hitter James Wood, who stole second and advanced to third on a wild pitch. As he had problems with the PitchCom pitch-calling system, Rodón was then called for a balk before his next pitch, sending Wood home.

“After the first one I was trying to lock in,” Rodón said. “But the balk, I was pissed about it. I didn’t step off soon enough. The PitchCom wasn’t working. It was what it was. I should’ve stepped off first before confronting the PitchCom, and I gave up a stupid run there, so that was pretty upsetting. It wasn’t my best.”

Rodón was visibly frustrated by the chain of events, pleading his case passionately to home-plate umpire Tony Randazzo to no avail. He’d allowed two runs before recording an out.

“It’s definitely frustrating when you’ve been using something and you have a good flow with it and the timing of things,” catcher Austin Wells said. “When that happened, we kind of had to flip the switch.”

The Yankees said they’d had trouble with the PitchCom system at Nationals Park all week.

“More so than usual,” Boone said. “We were having a lot of issues with it. I don’t know what the deal was.”

Said Rodón: “In Game 1 and Game 2, we were having issues with the PitchCom, but I wasn’t expecting it this start.”

Rodón’s ERA in the first inning this season is 7.67 in 27 innings.

His ERA in all other innings is 3.54 in 119 1/3 total innings.

“It’s tough when we’re down five runs and I’m not really giving the team a shot at winning,” Rodón said.

Though Rodón ultimately settled in, the Nationals used five stolen bases to help scrap five runs off the left-hander in 5 2/3 innings. Gore, meanwhile, held the Yankees to Jazz Chisholm Jr.’s solo homer and Aaron Judge’s RBI single over six innings. New York fell to 17-22 against left-handed starters this season. It is 61-34 against right-handed starters.

“It’s been weird,” Boone said. “We’ve had two stretches like this this year, where it’s just been lefty after lefty, and then you don’t see one for a few weeks.”