Moore had confirmed the club's agreement with Arguelles, a left-handed pitcher from Cuba, a month ago during the Winter Meetings. At the time, he figured it might be Christmas before the deal was officially completed.
Well, Happy New Year.
The Royals announced on Thursday that Arguelles had signed a five-year Major League contract. Although terms were not revealed, it's known the deal is worth nearly $7 million -- $6.9 million to be exact.
It took time for Arguelles, a Cuban defector who has been in the Dominican Republic, to clear immigration procedures and come to Kansas City for a physical by team doctor Steve Joyce.
Arguelles fills the Royals' winter roster as the 40th player and will be in the Major League Spring Training camp in February, but don't look for him on the Opening Day roster.
Moore said that while Arguelles will be in the club's Surprise, Ariz., complex next week for strength and conditioning work, he won't be doing any throwing.
"He's been throwing basically for 17 months straight. So he needs some time off. We don't want him picking up a ball for at least another month so that's going to put him behind in Spring Training," Moore said.
"There's no chance for him to make our Major League team out of Spring Training. We don't expect that, we don't anticipate that. He'll start somewhere in our system -- he's 19 years old, so it'll be like getting a sophomore in college basically."
Realistically, Arguelles is likely to start the season in Class A with Wilmington or another affiliate.
Arguelles, who turns 20 next Tuesday, was signed by the Royals after a long period of training, workouts and tryouts in front of Major League teams. Moore scouted him personally in the Dominican.
"He's 6-4, 225 and very athletic, very competitive," Moore said. "He's got an above-average fastball and changeup, a curveball and slider. He's certainly a top pick if he was in the Draft this year."
The future seems bright.
"We feel he'll be a top-of-the-rotation pitcher at some point in his career," Moore said.
Arguelles defected with shortstop Jose Iglesias, who signed a four-year, $8.25-million deal with Boston, at the World Junior Championships in Edmonton, Canada, in July 2008.
Prior to that, he pitched for the La Habana Vaqueros in the Cuban National Series and for the Cuban team at the Pan American Junior Championships in 2007, winning the gold medal game with eight shutout innings against Mexico.
"He's pitched well in international competition," Moore said. "We'll move slow with him and go from there."
Moore views Arguelles as having a good temperament.
"You'll love him," Moore said. "He's got a great heart and a great face. He's very competent and very respectful. He's a wonderful kid."
Arguelles should get good support from, among others, Royals catcher Brayan Pena who defected from Cuba several years ago and has adjusted well in the United States.
The tall lefty will be in Spring Training with another recent signee, right-hander Aaron Crow, who was the Royals' top Draft choice last June. In September, Crow signed a three-year deal worth $3 million plus incentives.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.