You wouldn’t know it by their 17-11 August record, nor by their 100 percent Playoff Odds, but this has been a bit of a turbulent season (again) for the talented Nationals. They’ve gotten some very good luck—like Brandon Phillips blocking a trade to Washington this winter, forcing the team to move on and sign Daniel Murphy; like Wilson Ramos suddenly becoming the star-caliber catcher for which first the Twins, then the Nationals had waited so long—but also some bad breaks, like Stephen Strasburg’s continued injury problems, and Bryce Harper’s (possibly injury-driven) two-month hiatus from Harperness. They’ve had to rebuild their bullpen on the fly, and navigate some odd early-season decisions by Dusty Baker.

Maybe the oddest (and certainly the worst) of those decisions early on was really a series of them: Baker wrote in Ben Revere and Michael Taylor as his leadoff men for the huge majority of the first half. Many things (like Baker batting Harper and Murphy consecutively, and Harper’s mid-season slump, and Ryan Zimmerman’s battles with injuries and ineffectiveness) have held back the Nationals offensively at times this season, but their leadoff hitters were the top reason for their occasional struggles to score. There’s no shortage of offensive talent here. Harper, Murphy, Ramos, Jayson Werth, and Anthony Rendon are a great start if you’re trying to build a dominant lineup. The problems early on were problems of sequencing: not enough guys on when Harper and Murphy socked tons of extra-base hits, too many stranded when Zimmerman came to bat in the heart of the lineup.

The Zimmerman problem solved itself. He missed three weeks in the middle of July, came back for a week, and went down for three weeks more. The Nationals’ efforts to replace him were half-hearted and wholly unsuccessful (Clint Robinson doesn’t have an extra-base hit since the All-Star break, for instance), but simply plucking him out of the picture forced Baker to push some people up, and that meant that often, Werth, Harper, Murphy, Rendon, and Ramos could bat in some uninterrupted order. The other thing it meant, as it turned out, was an opportunity, an opening into which the savior of the Nationals’ season stepped.

That’s a little strong. Trea Turner’s 2.4 WARP don’t explain the gap between them and their tepid field of NL East competitors. Still, that’s the way it feels. Since Turner took over as the Nationals’ leadoff man after the All-Star break, the team is scoring nearly half a run more per game. Revere has a .220/.271/.309 line in 55 games at the top of the order. Taylor has batted .200/.242/.371 in 34 games there. Turner has played 38 games in the leadoff spot, and batted 182 times in them. He’s batting .343/.357/.531 in those plate appearances. Turner’s .439 OBP in 41 first-inning plate appearances is nearly double the .222 mark Revere has posted in 64 such chances. Both Turner (44 percent of the time) and Revere (41 percent) score quite often when they reach base, which is what happens when you hit at the top of a lineup as deep and as good as this one. The disparity between them as hitters is huge; it’s the difference between a qualified National League leadoff hitter and a grossly underqualified one. With the guys the Nationals have bunched up behind that leadoff spot, it’s particularly crucial to have someone who belongs.

Of course, Baker could have solved this problem a long time ago. A lineup of:

Werth Murphy Ramos Harper Rendon Espinosa Zimmerman Revere

would have meaningfully outscored the lineup he was putting out there in the first half. That’s not how Baker manages, though. He would never have seriously considered assembling such a base-clogging, aged top of the order. He has a need for speed in that top spot, and Revere filled it. That’s why Turner is so uniquely valuable in Washington: He’s a Baker-style player, but he’s good enough that the shape of his production matters relatively little.

That might not be true forever, or even for the rest of the season. Turner’s insanely low walk rate (six of them, six!, in 195 plate appearances on the year) is a blinking alert, a reminder that if he should find the league’s next round of adjustments tough to handle, things could still get ugly fast. If that happens, the picture gets muddy again. The Nationals’ run prevention has been as much worse since the break as their run production has been improved, and with both Strasburg and Sammy Solis banged up, that might not change soon, or quickly. They can’t afford to give back the gains they’ve made on the scoring side of the ledger. As long as Turner keeps doing what he’s doing, though, Baker will keep creeping toward the NL Manager of the Year award (deserved or not).