WASHINGTON -- Even as the Los Angeles Dodgers continue their insistent search for starting pitching before the July 31 trade deadline, their top two starters keep raising the bar for how dominant Dodgers pitching can be.

Zack Greinke kept putting up zeroes -- more than 43 innings worth of them by now -- in the Dodgers' 5-0 victory against the Washington Nationals on a steamy day near the Capitol. Meanwhile, about 150 miles north of here, the Dodgers sent another scout to watch Cole Hamels struggle through three innings in Philadelphia.

Greinke hasn’t given up a run since June 13 and he’s now 16 innings short of Orel Hershiser’s 1988 major-league record for consecutive scoreless innings. Sunday was, in a way, his most impressive outing of the year given the punishing heat, the mid-game catching change after Yasmani Grandal caught a foul tip on the jaw and the season-high 119 pitches he threw.

And yet, always blunt, Greinke acknowledged the Nationals’ injury-depleted lineup wasn’t his most trying challenge this season. He and Clayton Kershaw managed to strike out 25 Nationals in their 16 shutout innings this series.

Until this weekend, the Dodgers hadn’t won a series on the road against a winning team all year. Greinke settled the question of who has been the most dominant pitcher in the league this year by out-pitching Max Scherzer, who was far from shabby himself over six innings. Greinke lowered his major-league best ERA to 1.30, a pretty skimpy number with August just a stone’s throw away.

Whereas Kershaw simply hones his three pitches to where they become nearly unhittable as the season progresses, Greinke dominates with a diverse array of pitches, speeds and locations. They share some common traits, though. They can throw the ball wherever they want it to go.

“It’s weapons,” Dodgers manager Don Mattingly said when asked to explain Greinke’s run. “The more weapons you have, the more you have to be able to go attack guys. You can’t attack all guys the same. One guy, it might be more sliders, some it might be the fastball to one side, or the other side. If you can mix all these different weapons, it puts guys in a bind. It’s hard to cover all that.”

The Dodgers have known for a while that Greinke and Kershaw were the least of their concerns, but they’d like to add at least one more dependable starter in the next couple of weeks. That’s why they dispatched scout Scott Groot to continue to get an in-person look at Hamels on Sunday amid mixed indications over whether the Phillies will actually move the left-hander by the non-waiver deadline. The Dodgers earlier sent director of player personnel Galen Carr to have a look at Hamels, according to a report, so their interest is more than due diligence at this point.

When Kershaw saw general manager Farhan Zaidi chatted with reporters before Sunday’s game, he jokingly asked, “Who are we getting on the 31st?”

They certainly don’t need a No. 1 or 2 starter. Greinke (9-2) lowered his ERA to 1.30 while striking out a season-high 11 batters over eight innings, giving up three hits and walking one batter. With temperature in the mid-90s and the air dripping with humidity, Greinke admitted he had no interest in batting when his spot in the order came up in the seventh inning.

Greinke loves to hit, so you know it had to be miserable out on the field. Nevertheless, he did bat -- and singled to left -- before getting a little breather while “God Bless America” played. Not only did he get through the seventh without giving up a run, he slowly made his way to the mound for the eighth, too, and that was important since the Dodgers have struggled this season covering the innings before closer Kenley Jansen can be used.

Greinke said he’s not thinking about his scoreless innings streak and this might be the rare situation when an athlete who claims something like that is actually telling the truth. Here’s how he describes this run he is on: “Just not making a bunch of mistakes and making good pitches.”

The Nationals couldn’t argue with that, though they could argue with umpire Bill Miller’s enormous strike zone. A couple of Dodgers hitters had issues with it, too, but Bryce Harper nearly got himself ejected striking out in the seventh inning after he thought he had walked.

Greinke turned around and watched the debate, a bemused little smile on his face. He has been watching a lot of frustrated hitters lately.