Feldman, who allowed four hits, three walks and two strikeouts, is now 9-3 with a 3.59 ERA on the season. Take out his three relief appearances and Feldman has a 3.04 ERA in 16 starts since joining the rotation.
"Feldman matched the best pitcher in baseball and threw an excellent ballgame," Rangers manager Ron Washington said after the his club finished its sixth shutout of the season.
Greinke came into the game leading the AL with a 2.08 ERA and actually nudged it down to 2.04 by holding the Rangers to one run in seven innings. Marlon Byrd delivered that run by smashing a first-pitch curveball over the left-field wall with one out in the fourth inning.
"I know he wished that pitch was in a better spot," Byrd said. "That was something we needed, and Feldman took it from there."
Greinke had beaten the Rangers, 2-0, with a shutout in Arlington back in April.
"He's having a great season," Feldman said. "He threw the ball well tonight. That's a pretty standard outing for him. There was not much room for error, but that didn't change what I was doing. This time I was able to keep my pitch count lower and go deeper in the game."
He did with a four-pitch arsenal. Feldman has been relying mainly on a sinker and cut fastball for the most part this season, but he was able to mix in a decent breaking ball and changeup as well.
"He used his changeup more and had a nice little breaking ball going," catcher Taylor Teagarden said. "I figured Greinke was going to do his usual seven or eight innings and allow zero or one run. At the same time, I was expecting Feldman to do the same."
"You gotta give [Feldman] some credit, too," Royals catcher Brayan Pena said. "He threw a pretty good game also. For you to outpitch Zack, you gotta throw pretty good. He did a great job."
Feldman also helped out with his defense. In the fourth inning, Mark Teahen hit a little chopper to the left of the mound. Feldman jumped on it, barehanded and threw blindly to first base to get the out.
"I don't know where that play came from," Feldman said.
The eight innings were the longest Feldman has gone in 42 Major League starts. He went seven innings on five occasions in 2008, but 6 2/3 innings was his longest outing this season until beating the Royals. When Feldman retired Royals leadoff hitter David DeJesus and No. 2 hitter Willie Bloomquist for the final two outs in the eighth inning, it marked the first time this season he has faced an opposing hitter four times in a game.
It only happened twice last year as well.
"I hope I can build on this and make it more of a regular thing getting us deeper in the game," Feldman said.
He almost got a chance for a complete game. The Rangers gave him a little cushion in the eighth when Byrd walked with two outs and Hank Blalock doubled him home. A couple of more runs and Washington would have let him go for the complete game. But in a two-run game, Washington felt Feldman had done enough.
Beating the AL ERA leader certainly qualifies as just that.