ST. LOUIS -- Hunter Strickland sat and stared into his locker. More than 15 minutes had passed since the end of the Nationals' 4-2 loss to the Cardinals at Busch Stadium on Monday night, and even more time had passed since Strickland surrendered the two-run single to Marcell Ozuna in the seventh inning that provided the difference. And yet, Strickland sat still there, almost dejected, as a few of his teammates, including relievers Roenis Elías and Fernando Rodney, patted him on the back to console him as he considered, perhaps, just how the decisive inning unraveled.

Strickland entered a tie game in relief of Sean Doolittle, who got the first two outs of the seventh but left with Dexter Fowler on first base so Strickland could face Paul Goldschmidt.

• Box score

Fowler promptly stole second base, then Strickland walked Goldschmidt on eight pitches. A wild pitch allowed both runners to advance into scoring position. Then Ozuna -- who drove in all four runs for St. Louis -- continued to torment the Nats, ripping a two-run ground-rule double down the left-field line to put the Cardinals ahead.

“The walk and then the other wild pitch that moved them over, all of it, it's all bad,” Strickland said. “There's no positive in that outcome for me personally. First and foremost is that walk, because that's the guy I've got to get out. That's the guy I was brought in for, and I can't give him a free base.”

The loss leaves the Nationals considering just how quickly they arrived at this point, where a playoff spot that very recently seemed all but assured is suddenly in jeopardy.

On the morning of Labor Day, Washington had been the hottest team in baseball for three months, with a 4 1/2-game lead for the first National League Wild Card spot and a comfortable seven-game cushion for a place in the game. After Monday, however, the Nationals have dropped nine of their past 14 games, reducing their lead over the Cubs for the top Wild Card berth to just a half-game, with just a 1 1/2-game advantage over the Brewers to even participate.

• Wild Card standings

“We played the same when we were 19-31 as we [did] when we were three games up, or wherever we were,” first baseman Ryan Zimmerman said. “We have, what, [13] games left? Go out and play those games and see what happens. You can’t control anything, so there’s no reason to think about it.”

The Nationals are still in position to control their own fate, especially during this three-game series. If they win the next two games, they could knock the Cardinals out of the NL Central lead, leaving the two teams to square off in that win-or-go-home matchup. But if the Nats can't keep pace with the NL Central clubs battling for position, they could quickly find themselves on the outside looking in.

Their grip on a playoff spot is slipping, and the NL Wild Card race is suddenly a lot tighter.

“I think it's important for us to stick together,” said starter Stephen Strasburg, who gave up two runs in five innings. “Again, there's going to be highs and lows over the course of the season, and we've got to do our best to flush this one and come out ready to play tomorrow.”