Kila Ka'aihue walked with the bases loaded with two out in the ninth to force in the winning run.
Royals starter Edgar Osuna, a Rule 5 draft pick from the Atlanta Braves, gave up four runs on five hits and two walks in three innings. The 22-year-old left-hander walked two and struck out two in three innings. He has a 10.00 ERA in four outings, allowing 11 hits and 10 runs in nine innings.
"Just a bad day," Osuna said. "I was trying to be cute and so that's what happens."
Osuna threw only 37 of his 63 pitches for strikes.
"We wanted to extend him a little bit today," Royals manager Trey Hillman said. "He didn't go as many innings as we were hoping he would because he simply had too many pitches. It didn't look like game sped up on him, he just couldn't command his pitches."
Osuna began by walking the first two batters, but got out of the first when Jose Lopez grounded into an inning ending double play. He retired the first two batters in the second inning, but then gave up two runs on four consecutive hits.
"You always have some pressure even when you're playing Little League," Osuna said. "When you're playing up here, you've got pressure. It's just baseball and I'm trying to do what I've been doing before, nothing different."