Only three others have done it since 1974, according to STATS Inc.: Calvin Pickering on Aug. 22, 2004, vs. Texas; Yamil Benitez on July 24, 1997, at Minnesota; and Jon Nunnally on April 29, 1995, vs. New York. Moore is the first Royals player since Benitez to homer in his first plate appearance (Pickering walked in his first trip to the plate).
Moore's blast to left in the third inning gave the Royals a 1-0 lead in what became a 15-4 loss to Cleveland.
"That felt really good, count 2-0 and got a fastball I could handle, put a good swing on it and put it out of the park," Moore said.
It was Moore's sixth Major League homer; the rest came with Seattle.
"I thought he did a nice job of receiving the ball, blocking the ball in the dirt, hit a home run," Royals manager Ned Yost said. "Looked good, I'm was impressed with him."
Moore handled right-hander Jake Odorizzi in his big league debut because he'd caught him with Triple-A Omaha this year. Odorizzi pitched five scoreless innings before giving up three runs in the sixth.
"He held his composure from pitch one until he got yanked out of the game. I thought he did a tremendous job," Moore said. "As soon as he starts getting that ball down in the zone consistently, which I know he can do, he's going to be perfectly fine."