Before the storm — before Nationals Park filled with driving rain, leaving fans shrieking and wet on the concourse, their phones lit up with one tornado warning, then another — Patrick Corbin knelt to the mound and stared at it.

Corbin knew that, behind him, Max Muncy’s grand slam was hurrying past the fence. He just didn’t face it until the damage was done, the homer undoing a tie in the fifth and final inning, pushing the Los Angeles Dodgers to a rain-shortened, 6-2 win over Corbin and the Washington Nationals.

The skies opened again at 9:02 p.m., forcing the grounds crew to sprint toward the tarp and cover the field before the top of the sixth. Then the game was called at 10:18, after Muncy rocked that hanging pitch to the second deck in the Dodgers’ decisive, five-run fifth. The Nationals had tried to beat them with Alex Avila, their backup catcher, playing second base; Starlin Castro, their third baseman, making his first start at shortstop since 2019; and Josh Harrison, their second baseman, bouncing between third and second to shrink Avila’s defensive influence.

Instead, in a matchup of the last two World Series champions, the Nationals’ four-game winning streak was snapped and they dropped to 40-39, still two games behind the New York Mets in the National League East. Their consolation was staying dry.

“It’s unfortunate,” Manager Dave Martinez said, unintentionally describing the whole day. “Corbin, I thought, was pitching really well. And then all of a sudden he gives up a grand slam.”

How did Avila wind up at second for the first time in his career? On Wednesday, in a 15-6 win over the Tampa Bay Rays, infielders Trea Turner and Jordy Mercer suffered what appeared to be minor injuries. Turner, Washington’s star shortstop, jammed his left middle finger while sliding into third base (an effort that sealed his third career cycle). Mercer, a veteran utility man, the club’s next option at every infield position, was slowed by a cramp in his right quadriceps. And the current minor league depth is not, well, deep.

The only other infielders on the 40-man roster are Carter Kieboom, Luis García and Yasel Antuna. But Kieboom is dealing with a knee injury, and García is on the injured list after hurting himself while swinging last Friday. Antuna, 21, has never been to the majors. Adrián Sanchez is on the IL, too, and could have played first, second, third or short against the Dodgers if he were available. Jackson Cluff, an infielder with the Class AA Harrisburg Senators, is also unavailable because of injury. Martinez hinted that an immediate solution in the middle infield could come either from within or outside the organization.

“We’re looking at other options,” said Martinez, who indicated that Turner could miss at least a couple of games while the swelling in his finger subsides. “Hopefully we can do something by [Friday].”

But in the absence of any moves Thursday and in the first of four games with one of the sport’s top teams, the Nationals had a very odd alignment. Afternoon rain kept Avila from taking grounders at the new position. Across 13 seasons, Avila, 34, had 924 appearances at catcher, 46 at first base, three as a pitcher and one at third. No wonder he smiled through his jog out for the first.

The Nationals’ plan — or the plan within the plan — was to shift Harrison to where batters would pull the ball. When right-handed hitters were in the box, then, they left him at third and Avila at second. When left-handed hitters were up, they flipped Avila to the left side of the infield. The only breaks from that logic were a soft liner in the first and Cody Bellinger’s chopper to Avila in the second, with Avila standing where a shortstop normally would. And Avila handled both plays, that grin stuck on his face.

“I thought Davey and [bench coach Tim Bogar] did a nice job as far as trying to hide me out there a little bit,” said Avila, who borrowed a glove from Mercer. “But at the same time, I was just trying to have fun with it and try my best not to embarrass the team.”

Yet the Nationals, as they were, couldn’t match the Dodgers for five full innings. They did nudge ahead in the first, once Kyle Schwarber led off with a double against opener Víctor González and Juan Soto singled him in. Then they went ahead in the fourth, once Josh Bell led off with a single against Tony Gonsolin and Castro scored him on a hit to center. The Dodgers, though, made use of one error and Corbin’s mistake to Muncy.

In the fourth, Harrison fielded a grounder at third and threw wide of second, pulling Avila off the bag to put runners on first and second with no outs. Three batters later, Albert Pujols singled in the Dodgers’ first run. Then A.J. Pollock led off the fifth with a solo homer, and Muncy’s bat broke the dam. Corbin loaded the bases by yielding a single to pinch hitter Steven Souza Jr., walking Chris Taylor and yielding another single to Justin Turner. Muncy just finished the job.

With the benefit of hindsight, Martinez could have managed the fourth and fifth as if they were the eighth and ninth. Storm warnings were buzzing every iPhone in the park. The air cooled, and there was distant thunder. So why not pinch-hit for Corbin with two on and two outs in the fourth and the Nationals up a run? Or why not hook Corbin for closer Brad Hand in the fifth, treating the inning like a save situation?

“We had reports saying that, for us, it was going to not happen until a little while later,” Martinez explained. “And then the next thing you know, we got [Wander] Suero in the game, and they said: ‘Hey, it’s coming.’ Then we heard sirens going off as we were going inside the clubhouse.”