After second-year starter Matt Shoemaker, the runner-up in American League Rookie of the Year Award voting last season, warmed up a second time after the swarm of bees delayed the start of the game by 10 minutes, the Royals got on the board on a two-run homer by Eric Hosmer.
In the bottom half of the inning, the Angels responded with consecutive singles by Trout, Albert Pujols and David Freese to send their first run across the plate in what turned into a three-run first against right-hander Edinson Volquez, making his Royals debut. The Angels scored their other two runs that inning when Erick Aybar reached on an error and C.J. Cron delivered a sacrifice fly.
The Royals entered the ninth trailing, 4-2, but a four-run frame -- keyed by Orlando Calixte's two-run triple and Ryan Jackson's go-ahead RBI single -- helped K.C. remain unbeaten (5-0) in Cactus League play.
"You like to see that energy," said Royals manager Ned Yost of the four-run rally in ninth. "We got some big hits. And it was a well-pitched game."
Shoemaker settled down to finish his first outing of the spring with three innings pitched, allowing the two runs on four hits.
Volquez, meanwhile, allowed three runs, only one of them earned, on three hits while striking out one.
"I felt really good," Volquez said. "My breaking balls were outstanding. I was a little up in the zone, but it was OK."
The swarm of bees was removed by a beekeeper in the middle of the fourth inning, causing another delay of about 10 minutes.
Up next: The Royals will send out left-hander Jason Vargas for his first outing of the spring as they travel to Maryvale to play the Brewers at 3:05 p.m. CT on Monday. The game can be heard on Gameday Audio.
John Schlegel is a national reporter for MLB.com. You can follow him on Twitter @JohnSchlegelMLB. This story was not subject to the approval of Major League Baseball or its clubs.