SAN DIEGO (AP) -- After his team hit five home runs on Saturday, Mike Moustakas was ready to keep the power surge going Sunday.
Moustakas hit two home runs and Jake Junis pitched seven-plus solid innings to help the Kansas City Royals beat the San Diego Padres 8-3.
Alex Gordon and Eric Hosmer also homered for the Royals.
"The offense gave us a big lead and Junis pitched on the attack," Royals manager Ned Yost said. "He executed pitches and had a really, really good slider. He held the fort for us."
Facing rookie Dinelson Lamet (2-2) Moustakas hit a three-run home run in the first that gave the Royals an early 4-0 advantage, and a solo homer in the eighth, his 17th this season.
"I saw it out of the hand and knew it was up and I tried to put a good swing on it, and it ended up carrying out of the yard," Moustakas said. "It definitely wasn't something that I was looking for, but when I saw it up I put some good wood on it."
Gordon homered in the fourth, a solo shot, and Hosmer added a two-run homer in the fifth to put Kansas City on top 7-1.
"He's really locked in," Yost said of Moustakas. "He is really putting together a great season this year power-wise. He is really seeing the ball well and driving the ball to all fields with power."
Junis (2-0), who lasted three and two-thirds innings in his previous start, allowed three runs, all on solo homers, on six hits over a career-best seven-plus innings. He struck out six and walked one.
"I felt like my off-speed was a little sharper today, and I was locating my fastball better than in previous outings," Junis said. "I was getting ahead and staying ahead."
Scott Alexander contributed two scoreless innings for Kansas City.
"Our bullpen has been used a lot," Moustakas said. "For (Junis) to come out and do what he did was unbelievable. We needed that big. He saved our bullpen."
Cory Spangenberg hit two solo home runs and Jose Pirela homered to chase Junis from the game in the eighth. Spangenberg recorded his second career two-homerun game for the Padres, who have lost seven of eight.
Lamet struggled for a second straight start after dominating in his first two. He gave up seven runs on six hits in five innings, while striking out six and walking one.
"I think more than anything today it was Lamet struggled with command," Padres manager Andy Green said. "That's gonna get you as long as the inning progresses."
Phil Maton made his major league debut for San Diego on the same day he was recalled from Triple-A El Paso with a scoreless eighth.
"Going in the game just didn't even seem real, just didn't want to hit the first guy, that's about the only thing that was going through my mind," Maton said. "Once I got that first pitch out of the way everything was okay."
"I'm still missing mistakes; this game is hard. I just try to come in and try to figure out how to get hits every day." Moustakas said.
Padres: OF Manuel Margot continues his recovery from a calf injury and was running in the outfield prior to Sunday's game. Margot will likely require a rehab assignment before returning.
Royals: C Salvador Perez left the game with left-side tightness in his rib cage area. Perez is expected to start Tuesday in San Francisco.
Padres: RHP Luis Perdomo (0-3, 3.50) will make the start for San Diego on Monday, looking to rebound from his last time out in which he gave up five runs in four innings at Arizona. Perdomo opposes RHP Bronson Arroyo of the Cincinnati Reds.
Royals: LHP Jason Vargas (8-3, 2.18) takes the mound at San Francisco on Tuesday. Vargas has won three straight starts and faces Giants LHP Ty Blach.