WASHINGTON -- For the first two innings on Monday at Nationals Park, the Nationals were on track to halt their recent struggles. They had entered the series against the Cardinals having lost three straight and 11 of their past 13 games, but they showed potential for a turnaround by jumping out to a 5-0 second-inning lead with Josiah Gray on the mound.

That early edge was cut to three runs in the third. By the fifth, it had turned into a one-run deficit. The final result was an 8-6 loss for the Nationals -- their first blown lead of five or more runs since Sept. 2, 2021, against the Phillies.

“Got to play 27 outs,” said manager Dave Martinez.

The first six outs were smooth for Washington. Gray faced just seven batters through two frames, striking out three, while his teammates swiftly jumped out against St. Louis right-hander Jack Flaherty.

The bottom of the first inning saw a leadoff double from former Cardinal Lane Thomas, a sacrifice fly from Luis García (one of his four RBIs) and hits by Jeimer Candelario, Joey Meneses (double), Corey Dickerson (two-run single) and Dominic Smith.

The Nats built on their three-run lead in the second inning, when Thomas added his second double and García plated Thomas and CJ Abrams on a single.

“The offense has been phenomenal with me out there pitching, and I can’t applaud those guys enough,” said Gray. “But I’ve just got to be better and not squander a five-run lead and just be able to go out there and give the team solid innings.”

Gray ran into his first hiccup in the third, when he allowed a line-drive RBI triple to Tommy Edman and a ground-ball RBI single to Paul Goldschmidt. After both teams were scoreless in the fourth, Gray wanted to work a fast fifth inning. The goal was to get his teammates back at the plate quickly in hopes of prompting an exit for Flaherty.

Instead, Gray opened the frame by giving up a double to Paul DeJong and a single to Edman. Then came the home runs. Brendan Donovan belted a game-tying three-run dinger a Statcast-projected 402 feet to right-center field, and Goldschmidt followed with a 406-foot go-ahead homer to left field.

Gray retired the next three batters to prevent further damage, but his outing was over after five innings with six strikeouts and six runs on nine hits and one walk. The hits and runs allowed were season highs.

“They’ve given me big leads a lot of times this year,” Gray said of his teammates. “... I just didn’t do my job there. So I definitely feel for the offense to go out there and put up five runs in the first two innings and for me to give that back. I’ve just got to bear down and just be a little bit better.”

The Nationals dropped to 20-14 on the season when scoring first and 3-37 when trailing after six innings. They matched the Cardinals with 11 hits but went 2-for-7 with runners in scoring position.

“We came out hot swinging,” said Thomas. “The middle of the game, I thought guys still were swinging it well -- CJ's hard lineout, Dom swung the bat good all day. It’s just one of those days. It just sucks when those balls don’t get through, because it was with guys on, too.”

An RBI groundout by García in the seventh and a two-out ninth-inning single by Abrams had Martinez encouraged by the late efforts after the early lead was erased.

“They’re playing hard, as you can tell by the last inning there,” Martinez said. “We’re still working good at-bats. … They’re grinding. Sometimes you see the best out of guys in moments like this, and I’m seeing it. These guys are not quitting. They’re going out there, they’re playing hard, they’re trying to finish.”