"I definitely had a better idea of where the ball was going to go when the ball left my hand," Anderson said. "As opposed to last time when it left my hand and I was like, 'Ooh, I'm not sure where that's going to be.'"
Meanwhile, right-hander Chris Young and left-hander Travis Wood, battling with Nathan Karns for the Royals' No. 5 spot in the rotation, each worked two scoreless innings.
Wood gave up an infield hit and an unearned run in his second inning of work.
"He changed speeds really good," Royals manager Ned Yost said of Young. "His slider was really good. He moved his fastball around, effectively up. And Wood the same way -- changed speeds and his command was excellent."
After the game, Rockies manager Bud Black said he was not sure Hosmer's drive should have been called a homer and he discussed the call with the umpires.
"They called it a home run, but it was not a home run," Black said. "The ball hit the top railing, but the umpires told me it went over the fence and that it hit the grass [berm]. So I said to the umpire, 'How does the ball go 20 feet up in the air when it hits the grass? That's hard grass.'"
Up next for Royals: Listen live on Gameday Audio as right-hander Ian Kennedy, likely the No. 2 starter this season, makes his spring debut when the Royals travel to Glendale to play the Dodgers on Friday at 2:05 p.m. CT. Right-hander Josh Staumont and his 100-mph fastball also will pitch.