Francoeur's homer cleared the high center-field wall 420 feet from home plate. Wilson said he tried to slip a first-pitch fastball past his former teammate in Texas.
"In spring training you have to take everything with a grain of salt," Wilson said. "The infield is a little bit hard. The ball travels really well. The adrenaline isn't quite there."
"Sometimes there are some funny circumstances that happen. You have these big innings and stuff like that. I just look at it as part of the process," he said.
Angels manager Mike Scioscia said he was a bit concerned about the performance of his starting staff this spring.
"With our rotation, some guys aren't where they need to be," Scioscia said. "I sure hope as we get to the later stages of Arizona we can get them where they need to be."
Wilson estimated his pitch count to be around 80, the amount the Angels wanted from him. He then went into the bullpen and threw a few off-speed pitches to "get the feel right."
Shields gave up for nine runs and 11 hits by the Angels in five innings.
"He was struggling to get his tempo," Royals manager Ned Yost said. "He's pitching a lot of those guys backward. They're not going to pitch these guys the way they do in the regular season."
Shields, the Royals' opening-day starter, went 15-10 with a 3.52 ERA with Tampa Bay last year and was acquired in a seven-player deal over the offseason.
"The ball was flying pretty good today," Shields said. "I made some pretty good pitches that they were hitting. The first couple of innings were not so great. After that I settled down. My direction to the plate was terrible."
Hosmer, Alcides Escobar, Salvadore Perez and Chris Getz each had two of Kansas City's 14 hits. ... Trout, Trumbo, Alberto Callaspo and Vernon Wells each got two of the Angels' 11 hits. Wells upped his spring average to .392. ... The Angels released utilityman Bill Hall. There was speculation that he could return to the team on a minor league contract. ... Angels star Albert Pujols, who's been slowed by plantar fasciitis, scored from first on Hamilton's triple. "He was running well," Scioscia said.