Alex Rodriguez finished 2-for-5 and homered for the fifth straight game to lead the New York Yankees over Kansas City, 6-3, in the finale of a three-game set at Kauffman Stadium. Jorge Posada recorded two hits, drove in two runs and scored once for the Yankees, who swept the series and have won five in a row. With Seattles win over Detroit, the Bombers are four games up on the Tigers and five ahead of the Mariners in the AL wild card chase. Robinson Cano added a pair of hits with an RBI and Wilson Betemit contributed a run-scoring double in the victory. Chien-Ming Wang (18-6) allowed five hits and three runs over seven innings for his fifth win in as many starts. He joined Bostons Josh Beckett as the only 18-game winners in the majors. "Hes our horse," said Posada. "Hes our number-one, so you try to get him some runs. I thought we had a very good chance of getting him some runs early. He struggled a little bit in that inning (the fourth), but we got some more runs." Kansas City reliever Brandon Duckworth (2-5) took the loss, charged with two runs in two-thirds of an inning. Starter Zack Greinke was tagged for six hits and three runs in just 3 2/3 innings in the no-decision. Alex Gordon drove in all three runs for the Royals, who have lost five straight. Against Duckworth in the fifth, Rodriguez singled and went to second on Joey Gathrights error. Hideki Matsui then walked, and John Bale came in to face Posada, who ripped him for a two-run double to put New York back on top, 5-3. In the eighth, the Yankees picked up an insurance run to go ahead 6-3. Posada led off with a walk and moved to second on Doug Mientkiewiczs sacrifice bunt. Cano stepped in and laced a single to center to plate the veteran catcher. Kyle Farnsworth pitched a scoreless eighth and Mariano Rivera hurled a scoreless ninth to nail down the win and earn his 25th save. Rodriguez put the Yanks ahead 2-0 in the first with his major league-best 52nd home run of the season. "I was planning on not pitching to him today and still went with that philosophy," Greinke said. "It was either going to be in the corner or off the plate and he still hit it. Thats just how good he is, especially right now." Cano began the second with a double and scored on Betemits double for a 3-0 advantage, but Kansas City rallied for three runs in the fourth on Gordons bases-clearing double. Game Notes New York won nine of 10 over Kansas City this season, and has won 16 of 19 over the last two years...Rodriguezs homer was the first given up by Greinke in 50 2/3 innings...Attendance was 24,910.