Davies was placed on unconditional release waivers by the Royals on Wednesday, clearing space on the 40-man and active rosters for catcher Salvador Perez, who was called up from Triple-A Omaha.
In 99 starts for the Royals from 2007 through this season, Davies had a 29-44 record and a 5.34 ERA.
"I wasn't happy with the way it turned out," Davies said. "I had stretches, but never to what I thought I could do and what they thought I could do."
Davies is currently on the disabled list for the second time this season with shoulder problems and likely would not have pitched again in 2011.
"He probably wasn't in a position to pitch the rest of the year and he's a free agent at the end of the season, so it was the obvious roster spot when we thought through it," general manager Dayton Moore said.
Davies was just 1-9 with a 6.75 ERA in 13 starts this season. Opponents were hitting .332 against him.
"Obviously this year has been really, extremely rough," he said.
Even so, Davies was encouraged by his last two starts before beginning his latest stint on the disabled list. On July 25 at Boston, he held the Red Sox to one run on five hits in six innings of what became a 3-1 Royals win. On July 18 against Chicago, he gave up four runs (two earned) in 5 1/3 innings against the White Sox and set a career high of nine strikeouts.
"Kyle is going to be a very successful Major League pitcher in the future," Moore said. "He's shown in spurts that he can be very good. He's very good, he's very talented. He's 27 years old and, assuming his health is good, he'll be a very successful pitcher."
Obtained from the Atlanta Braves on July 31, 2007, in a trade for reliever Octavio Dotel, Davies showed good velocity and movement on his pitches but battled constantly to command them, especially his fastball.
"It was just being able to harness it and getting better with it," he said.
Sent to Triple-A Omaha for stretches in 2008 and '09, Davies spent the entire 2010 season in the rotation and went 8-12 in 32 starts, 14 of them ranked as quality starts. Last winter, he avoided salary arbitration by signing a one-year contract for $3.2 million.
Moore and Davies have known each other since their days in the Atlanta organization. Davies was drafted in the fourth round of 2001, when Moore was in the Braves' scouting department.
"Dayton and I are good friends and go back a long time," Davies said. "And I love the majority of our players and have played for a good number of years here. I'm very, very thankful for everything the Royals have given me the opportunity to do at the big league level. And I have zero hard feelings toward anyone."
"I've known [Davies] since he was 17," said Moore, "but this is just part of the game."
Davies plans to continue his pitching career.
"I believe that I can," he said. "The first thing I've got to do, though, is get myself healthy."
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.