The Royals may or may not be interested in the 33-year-old right-hander, but Hillman -- who managed for five years in Japan -- certainly is well acquainted with Kawakami.
"Kawakami is a real good competitor," Hillman said. "I would say he's probably a three, four or five starter. He's not very big. It may have been last year or two years ago, he had some arm trouble early in the season but he came back real good and pitched very well."
He's pitched 11 seasons for the Chunichi Dragons, the team that beat Hillman's Nippon Ham Fighters in the 2007 Japan Series.
"He was one of the most difficult guys for us to do anything against in the Japan Series," Hillman said.
"He's not overpowering. He's typically 87 to 91 [mph], probably pitches at 88. He's a location guy but he can spin it and he can split it. His slider does have depth; his split is deceptive at times."
Last winter, the Royals signed Japanese reliever Yasuhiko Yabuta and also pursued starter Hiroki Kuroda, losing him to the Los Angeles Dodgers. Yabuta struggled and spent about half of his season in Triple-A.
"Kuroda was much more projectable than [Kawakami], both body and stuff-wise," Hillman said, "although this guy is a good pitcher."
Kawakami has expressed interest in the Boston Red Sox and the Tampa Bay Rays, and the Atlanta Braves also have been linked with him.
What degree of interest the Royals might have in Kawakami is uncertain.
"As far as whether we would have any interest, I'm sure our international guys have reports in on him," Hillman said. "As an opposing manager against him, I sure didn't like facing him. But, as we've seen with Yabuta, you just never know how that transition period is going to go."
General manager Dayton Moore was not available for comment.
"Dayton and I have not discussed him, but at some point in time, I would think that it's possible that we will," Hillman said.
Kawakami had a 112-72 record in his 11-year career with the Dragons. This year he was 9-5 with a 2.30 ERA and 112 strikeouts in 20 games.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.