''He's a great pitcher. That's an obvious for sure,'' Duffy said of his Dodgers counterpart, shortly after allowing one run over six innings in a 2-0 loss to Los Angeles on Tuesday night.
''He went out there and had great stuff, great command, as he usually does. His slider is so nasty,'' Duffy said. ''You can always pick up something from your opponents. I just want to go out and command the ball a little better next time.''
Duffy (4-7) allowed four hits and four walks but needed a season-high 105 pitches, forcing Royals manager Ned Yost to pull him to protect his surgically repaired shoulder.
''Personally I'm proud of the way I got through six,'' Duffy said. ''You can always do better. You eliminate that first inning and that first at-bat of the game, we're looking at a zero-zero tie. I tried to be strong through six. Command was erratic.''
That was hardly the case for Kershaw (8-2), who allowed six hits and a walk while striking out eight. The two-time Cy Young winner hasn't allowed a run in 21 1-3 innings, spanning his near-perfect game against Colorado on Wednesday - the only runner occurred on an error - and his previous start against Arizona.
Kenley Jansen pitched a perfect ninth for his 23rd save.
Eric Hosmer had a pair of hits for the Royals, the first with one out in the first inning to end any thought of Kershaw tossing consecutive no-hitters. Otherwise, their offense was sporadic, unable to string together enough runners to pose much of a threat.
''We had a couple of innings where we had runners at first and second and that was about it,'' Hosmer said. ''Guys like that, when they've got guys in scoring position or on base, they turn on it to a different level.''
The Dodgers plated their first run after Justin Turner tripled to lead off the game. He scored on a hard grounder by Gonzalez, which deflected off Duffy and toward second base for what nearly ended up being the game's only run.
Ethier's RBI single came off reliever Kelvin Herrera in the ninth inning.
Duffy needed 29 pitches to survive the first, and he wiggled out of jams each of the next four innings, too. But while he was gritty enough to keep Kansas City in the game, a lineup that has struggled to put up runs for the last week failed him again.
Kansas City has only scored 13 times while losing five of its last six.
Los Angeles had lost all four of its games played at Kauffman Stadium, including the series opener Monday night, when the Royals beat up on Zack Greinke, their former ace.
They had a much tougher time handling Kershaw.
Showcasing his mid-90s fastball, power curveball and devastating slider, Kershaw at one point retired eight straight. And even when he ran into trouble, he slipped right out of it.
Kershaw induced a double play after Hosmer's single in the first. He rallied from a 3-0 count to Alex Gordon to strike him out with a runner aboard in the sixth. In the seventh, he got Justin Maxwell and Alcides Escobar on groundouts to leave a pair of runners on base.
''That's the best slider we've seen,'' Yost said. ''That thing had teeth with a bite.''
In fact, the biggest blight on Kershaw's night may have been his walk to Gordon in the fifth inning. It was only the second he'd allowed to a left-handed hitter this season.
''It definitely wasn't easy tonight,'' Kershaw said.
It only looked that way.
''All night he felt like he was fighting it,'' Dodgers manager Don Mattingly said. ''His fastball command wasn't where he wanted it, but typical Clayton.''
NOTES: Dodgers SS Hanley Ramirez (sore right shoulder) was scratched from the starting lineup. ''Hopefully we'll have him tomorrow,'' Mattingly said. ... The Royals activated LHP Bruce Chen (bulging disc) from the 60-day DL, optioned LHP Tim Collins to Triple-A Omaha and designated LHP Donnie Joseph for assignment. ... Dodgers RHP Dan Haren faces Royals RHP James Shields in Wednesday night's series finale.