WASHINGTON -- Rockies right-handed pitcher Jon Gray believes part of his role is to provide glue when cracks appear. But as cracks grow to craters, Gray is having a hard time keeping his health together.

As he worked toward putting the Rockies back on track Wednesday, Gray sustained a bruised right calf on a second-inning line drive and left the doubleheader opener against the Nationals after struggling through four innings. After he was gone, just enough went wrong for the Rockies lose for the 15th time in the past 18 games, 3-2, at Nationals Park.

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Gray has put up the best overall numbers of any starter in the Rockies’ struggling rotation. But Wednesday, when Gray allowed just one run but tied a career high with five walks (one intentional) as his calf tightened, marked the second consecutive start that Gray was unwell. Battling a stomach bug July 17, he allowed 11 hits and six runs in 5 1/3 innings during a home loss to the Giants.

Gray has a 4.05 ERA -- one that was in the 3s before last week’s illness -- and for the most part, he has pitched like a guy who should be in a pennant race. But nothing has gone right for a while, and even he needs some mending.

“It is frustrating,” said Gray, who believes he will recover in time for his next start. “We know where we should be right now. We see problems pile up on top of problems. It’s not good. But I know we’re not the team that’s going to just give up on it. We’re definitely going to fight to the end.

“I just want to see everything come together like it has before. When everything’s working for us, we’re unstoppable. If we’re pitching well and hitting well at the same time, no one can beat us. But I haven’t really seen that team this year.”

Wednesday was more of the Rockies team no one wants to see.

Gray was firing fastballs at better than 97 mph and seemed headed for a nice day before Brian Dozier’s liner crashed off the outside of his right calf and ricocheted to first baseman Yonder Alonso for the second out of the second inning. Manager Bud Black and trainers visited Gray, and adrenaline pulled him through the third.

But in the fourth, he walked three, including pinch-hitter Gerardo Parra with the bases loaded to tie the game at 1. Considering that Gray had walked five in a game just twice in his career, the last time on Sept. 7, 2018, against the Dodgers, it was clear the calf was affecting him.

“It affected his control and command, as we witnessed in that inning,” Rockies manager Bud Black said. “By the time he got out of it, it was sore; painful. And Jon is tough. He tried to hang in there, but he said, ‘Buddy, I don’t think it was the right thing to do.’ So we took him out of the game.”

With the injury to his push leg, Gray sank too low in his delivery and lost the strike zone.

“It’s frustrating,” he said. “All my stuff was working early. I was attacking guys early. I tried to stay in attack mode, but things just weren’t the same. I knew it wouldn’t be a wise decision to keep myself in.”

Two Rockies relievers yielded homers on the first pitch -- Chad Bettis to Adam Eaton in the fifth, and Carlos Estevez to Anthony Rendon in the seventh. The Nats overcame a two-double, two-run game from first baseman Yonder Alonso in his first start since joining the Rockies on Tuesday, and two RBIs from Ryan McMahon.

It was the type of tight game that could draw out the type of pitching performance that, maybe, could push a team forward. But the current plight could have the Rockies making the tough choices that come with being a seller at the July 31 Trade Deadline.

“Once we get into rhythm, I don’t know if it’ll be a certain event that will happen in one of the upcoming games or something, but it’s gotta change for us -- very quickly,” Gray said. “We’re running out of opportunities.

“I know [trading off key players] is a possibility. I try to keep my mind away from it and just let it take care of itself. Just keep doing what I’m doing and see what I can do to help the team out. If we start worrying about things that haven’t happened yet, we’ll be in a bad spot.”