Cruz hit a two-run homer and the first-place Baltimore Orioles beat the Royals 2-1 on Thursday night to snap a four-game losing streak.
Cruz homered in the fourth after Chris Davis drew a walk to lead off the inning. It was Cruz's 12th home run, which is second in the American League to the 15 of Chicago White Sox rookie Jose Abreu. Cruz's 35 RBIs are tied for second in the AL.
"He's one of the best power hitters in the American League over the past five or six years," Royals manager Ned Yost said. "He's hit in a good hitter's park in Texas, but he's got power to all fields."
Wei-Yin Chen (5-2) limited the Royals to one run and seven hits over 5 1/3 innings with one walk and one strikeout. Chen, who is 5-1 in his past seven starts, was removed in the sixth after Salvador Perez walked and Alex Gordon singled with one out. Darren O'Day replaced Chen and struck out Danny Valencia and retried Johnny Giavotella on a fly to right.
Royals rookie right-hander Yordano Ventura (2-3) struck out nine and walked one in 6 1/3 innings, allowing two runs and seven hits. After Cruz's home run, Ventura retired the next 10 batters, striking out seven, including six straight at one stretch.
"He made a mistake to Nelson Cruz and it wasn't even a mistake," Yost said. "I think he threw a good fastball to Nelson. It was up and over the middle of the plate and he ambushed it."
Cruz hit the first pitch out to right-center from Ventura, who has a fastball that routinely hits triple digits on radar guns.
"We know he's got a great fastball," Cruz said. "He can get you quick. He's got great stuff. It was one of those at-bats that I got what I was looking for. We were trying to be aggressive and he was throwing a lot of first-pitch fastballs. I was looking for a fastball."
With a northwest wind blowing 15 mph and gusting up to 28, it was less than ideal conditions to hit a home run.
"You could have made some money off me if you'd have bet me that somebody could have gotten a ball out of here tonight," Orioles manager Buck Showalter said.
Valencia's sacrifice fly with the bases loaded in the fourth scored Eric Hosmer for the only run off Chen.
"Ventura pitched great," Giavotella said. "We just couldn't back him up with any runs."
Left-hander Zach Britton, who had not allowed a run in 7 1/3 innings in his past eight appearances, worked a perfect ninth for his first major league save. Showalter elected to go to Britton after closer Tommy Hunter blew his past two save chances.
"Guys graduate," Showalter said. "It was a good start and it's good to know that if we need him for a given night he'll be ready. We'll see how it goes from here."
The Royals did not have a baserunner off four Baltimore relievers, who retired 11 straight.
"Our pitchers did a really good job and we really needed this win," Cruz said. "Anytime you can win a game by one run it's huge. We feel like we can get something going."
The Orioles, who went 1 for 9 with runners in scoring position, threatened in the seventh and eighth innings, but came away empty.
Gordon, a three-time Gold Glove Award winner, threw out J.J. Hardy at the plate to end the seventh for his fourth outfield assist this season and his 58th since moving to the outfield in 2011. Hardy attempted to score from second on Nick Markakis' single.
Manny Machado and Adam Jones led off the Orioles eighth with singles off Louis Coleman, the third Kansas City pitcher. Kelvin Herrera replaced Coleman and struck out Davis and Cruz and retired Steve Clevenger on a grounder to strand the runners.
The Orioles recalled RHP Evan Meek from Triple-A Norfolk and optioned RHP Kevin Gausman, who lost a Wednesday start to Detroit, to the same club. ... Markakis snapped an 0-for-14 skid with three singles. ... Royals RHP Wade Davis has a stiff neck and was not available.