WASHINGTON -- The Nationals are undoubtedly playing their best baseball of the season, winning again on Wednesday afternoon after a walk-off, two-run homer from Trea Turner off Alex Colome in the ninth inning led the Nationals to a 6-4 victory over the White Sox.

It was Turner’s second walk-off homer of the season, even though he has only played 22 games, to extend Washington’s winning streak to a season-high four consecutive games. They endured another eighth inning collapse from the bullpen to take back-to-back games from Chicago at Nationals Park and sweep this brief two-game set, notching their fourth consecutive series win.

“Three weeks ago we probably lose that game,” manager Dave Martinez said. “And we end up winning.”

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Since dropping to their lowest point of the season on May 23, when they were a season-worst 11 games under .500, the Nationals have now rattled off wins in 9 of their past 11 games. They have trimmed the gap in the National League East from 10.0 games then to 6.5 games at the conclusion of Wednesday’s game. They are, however, still in fourth place, looking up at the Mets, Braves and Phillies, but the Nationals can feel fortunate no team in the division has taken off.

Some of this recent stretch can be chalked up to regression. This team was always more talented than its poor start indicated, but in the first two months of the year, it had to endure a lineup depleted by injuries, 2/5 of the starting rotation that was ineffective and the bullpen was on pace for one of the highest ERAs in MLB history. It seemed as if everything that could go wrong, did, with each mistake amplified into something larger.

“We've played good baseball all year, we've just been on the losing side because of something stupid each game,” Turner said. “Stupid mistakes are starting to go away and we're starting to play consistent and pitch when we need it, hit when we need it. We bailed our pitchers out today, but last week, they bailed us out. That's what good teams do. When you need to score one more run than the other team, no matter when it is, I think we've been able to do that lately. That's how you win.”

So, can the Nationals keep it up? Here are a few reasons for optimism and some reasons to be skeptical of this recent hot stretch.

Starting rotation firing on all cylinders

It always comes back to starting pitching in Washington and with this rotation, the Nats feel like they should have a strong chance of winning every night. Aside from the occasional hiccups, Max Scherzer, Stephen Strasburg and Patrick Corbin have been superb all season. And Erick Fedde has been filled in nicely as the team’s fifth starter recently. The difference lately has been Anibal Sanchez in the two starts since his return from the injured list. On Wednesday, he limited the White Sox to just one run in 5 1/3 innings with seven strikeouts and a walk proving his six-shutout inning outing last week against the Braves was no fluke. Since returning from the injured list, Sanchez owns a 0.79 ERA with 14 strikeouts and two walks.

“I feel comfortable with my location,” Sanchez said. “Everything that I worked on since I got back from the DL, has helped me to put my ball in the spot that I want.”

Lineup is rolling

There were days in May where Martinez had to ask around to see how many players he had healthy enough to write into the lineup each day, back when the injured list read like a who’s who of Nationals position players. Now healthy once again, the Nationals own one of the deepest and most dangerous lineups in the NL. Anthony Rendon has reached base in 21 consecutive games and is batting .360 with seven doubles, five homers and 19 walks during that span. Juan Soto went 3-for-4 on Wednesday and is batting .433 in his last 18 games. Howie Kendrick’s 10 home runs this year are his most since 2013. Kurt Suzuki has a hit in five straight games. Collectively, it’s a lineup that never feels like it’s out of a game and is capable of putting together a comeback at any point.

“It’s about time. It’s our time now,” Soto said. “Everybody’s put in something to win the game. Everyday everybody comes positive, bring the energy every time.”

Bullpen is still a daily landmine

“We're not going to win with three guys in the bullpen,” Martinez said following the game. “I can tell you that.”

It has been the Nats major flaw all season and nearly cost them Wednesday’s game. Martinez has so few relievers he will turn to and trust to close to close out games. It nearly cost them Wednesday when with a three-run lead in the eighth, Martinez tried to get a second inning from Kyle Barraclough and it backfired when Jose Abreu hit a two-run homer with two outs. Then, Martinez turned to Wander Suero for the second straight day, a situation Martinez wanted to avoid if possible, and then Suero surrendered a game-tying solo homer to the first batter he faced, Welington Castillo.

Martinez’s confidence in Tanner Rainey is growing and Matt Grace has been solid recently as a matchup lefty, but still the Nats bullpen is capable of such implosion at nearly any point. So yes, the Nats have trimmed their bullpen ERA with a string of good outings lately, but the unit still owns a collective 6.68 ERA, still more than half a run more than any other team.