HOUSTON - The Yankees kept the Astros, the major league leaders in home runs, in the ballpark.

And for the most part, they did a decent enough job with the American League steals leaders on the basepaths.

But what the Yankees had no answer for -- and they certainly have company in this regard -- was Dallas Keuchel, Houston's star lefthander.

The reigning AL Pitcher of the Month in April and May has struggled a bit this month, but he coasted in blanking the Yankees, 4-0, on six hits Thursday night in front of 28,643 at Minute Maid Park.

Keuchel struck out five in the first two innings on his way to a career-best 12 strikeouts. He matched his career high of 11 through six innings before picking up No. 12 in the ninth.

After Carlos Beltran reached on an infield single with two outs in the fourth, Keuchel retired the next 15 batters before Alex Rodriguez singled, Mark Teixeira drew Keuchel's first walk and Beltran singled to load the bases in the ninth. Jose Pirela, representing the tying run, then grounded into a forceout to end it.

Keuchel (9-3, 2.17) had limited lefties to a .141/.180/.200 slash line and righties to a slash line of .209/.272/.292 entering the game.

Adam Warren did not pitch poorly in defeat. The righthander, 3-3 with a 2.93 ERA in his previous seven starts, allowed three runs (two earned) and five hits in 52/3 innings. The Yankees (39-34) committed three errors behind him.

Chris Young, who had two hits, led off the game with a single to left, but Keuchel -- very much setting the tone for the night -- struck out Chase Headley, Rodriguez and Teixeira. The latter two were called third strikes, with Teixeira looking back at Joe West in irritation after his punchout, not the last time the Yankees would be upset with the plate umpire. (Girardi and bench coach Rob Thomson chirped at West after Headley was called out on strikes in the sixth.)

The AL West-leading Astros (43-32), who stung three balls in the first inning but had nothing to show for it, got on the board in the second.

After missing a homer down the rightfield line by inches, Luis Valbuena was hit by a pitch. Evan Gattis flied to right and Valbuena was erased when Colby Rasmus hit into a force play, but Preston Tucker then took a 2-and-0 fastball the opposite way down the leftfield line, deep enough into the corner to allow Rasmus to score from first for a 1-0 lead.

The Astros added an unearned run in the fourth. Jose Altuve, who came in third among all AL second basemen with 76 hits, led off by driving a 2-and-0 slider into left for his 13th double of the season. Valbuena followed with a ground shot that shortstop Stephen Drew booted for his fifth error of the season. Gattis' long fly to right allowed Altuve to go to third and Rasmus' sacrifice fly to right made it 2-0.

Houston tacked on in the sixth. Altuve reached on an infield single and, with Valbuena at the plate, took off for second. John Ryan Murphy's throw was wide of the bag and sailed into center, allowing Altuve to go to third. Gattis then banged a 2-and-0 fastball up the middle for an RBI single that made it 3-0.

Gattis added an RBI double off Chris Capuano in the eighth.