The skies were gloomy and overcast, but there was nothing but smiles and sunshine inside Kauffman Stadium Monday afternoon as the defending American League champion Kansas City Royals roughed up the Chicago White Sox 10-1 to claim their first Opening Day win in six seasons.

A lengthy pregame ceremony, in which every member of the Royals organization received a 2014 American League championship ring, did not faze starter Yordano Ventura, who at 23 years old became the team's youngest Opening Day starter since Steve Busby took the mound 42 years ago.

Ventura had it dialed in on cruise control through six innings, allowing just two hits and no runs.

Chicago's Jose Abreu lined a home run into the left field bleachers with one out in the seventh and cleanup hitter Adam LaRoche fouled off a pitch before Ventura jumped off the mound in obvious pain as he grabbed the thumb on his right (pitching) hand.

Manager Ned Yost and the team's training staff ran to the mound as Ventura rolled around in pain.

“I was running over to second and looked out at the mound and saw 'Ace' rolling around on the ground and thought, 'Oh my gosh, what happened,'” said third baseman Mike Moustakas, who had a homer, single and sacrifice bunt from his new No. 2 spot in the lineup (see related story). “It looked like he was hurting pretty good, and none of us knew what happened, especially since the ball was fouled off. It looked like he'd been hit, or something.”

The Royals announced later that Ventura experienced a cramp in his thumb and that the injury was not serious.

"He gets them all the time," Yost said in his postgame news conference. “When I saw it I figured he was cramping up, it was just worse than it usually is. Before that, everything was working for him. It was a good way to start the season – except for the cramp.”

Later, Ventura addressed the media and talked about his Opening Day start through interpreter and teammate Jeremy Guthrie.

"I felt it lock up on me," Ventura said. "I thought at first it was something really bad. I'm happy that it isn't, and I'm not concerned about missing any time with what happened. Just a cramp that surprised me, but I feel confident going forward.

"I have had them before, but never as serious as today. I've pitched through them without letting anybody know that I had them. This one was different."

Ventura gave up one run through six-plus innings and got the victory.

The lanky youngster, who just signed a five-year deal with the Royals, made his debuted in the national spotlight in last year's World Series, throwing seven scoreless innings in a 10-0 Game 6 win.

He said that none of the pregame ceremonies rattled him before his first Opening Day start.

“Nothing was going to distract me because I had a job to do,” Ventura said through Guthrie. “It feels good to do well in a big game. I came into the game feeling confident and my teammates did a great job playing defense and scoring runs for me.”

Catcher Salvador Perez drove home the first run of the game with a two-out double in the bottom of the second inning.

Lorenzo Cain added an RBI single and eventually scored on a wild pitch in a two-run third.

Moustakas' solo homer gave the Royals a 4-0 lead in the fifth and they blew the game open with a five-run seventh, with new left fielder Alex Rios' three-run homer the big blow of the inning after Alex Gordon’s two-run single dribbled through the infield.

Moustakas, Alcides Escobar and Omar Infante all finished with two hits each, and Rios had three in his Royals debut.

“I was proud of what I saw out there today,” Yost said. “We all saw this team grow up last year in the playoffs and that continued today. They were focused and they didn't get sidetracked by any of the ceremonies going on today. We expect to see some good things this season, and this was a great way to start.”