DETROIT — Royals manager Ned Yost likes to characterize designated hitter Billy Butler as a “hitter who can hit good pitching” and for validation points to Butler’s success against Detroit ace Justin Verlander.

Butler nicked Verlander for three hits in Monday’s 6-2 loss, which left him with a .396 career average (21 for 53) against a pitcher who looms as a strong candidate to repeat as the American League’s Cy Young Award winner. (Verlander was also the 2011 MVP.)

“Some guys are good hitters but can’t hit good pitching,” Yost said. “They’re good hitters, but when you face the elite guys with the overpowering fastballs, they’re not going to hit much. Billy, like (Detroit’s Miguel) Cabrera, can hit everybody.”

Dig just a little deeper, and it’s possible to argue Butler carries the biggest run-production responsibility in the American League.

Butler entered Wednesday’s game against the Tigers with a career-best 102 RBIs, which were 31 more than third baseman Mike Moustakas’ second-best total of 71.

Only one other player, Toronto DH Edwin Encarnacion, had a bigger lead – by one RBI. Encarnacion had 106 and a 32-RBI edge over Colby Rasmus at 74.

Viewed another way, though, Butler’s production was 43.7 percent higher than Moustakas; Encarnacion had a 43.2 percent edge over Rasmus.

The only club leader with a higher percentage lead than Butler was Seattle third baseman Kyle Seager at 44.6 percent over catcher Jesus Montero. But Seager had just 81 RBIs (to Montero’s 56).

Free-agent watch

The pledge earlier this week by owner David Glass to upgrade the Royals’ rotation in the offseason adds weight to tracking pending free agents and potential free agents.

Two Angels veterans – right-handers Dan Haren and Ervin Santana – could be among those available.

MLB.com reports, citing an unidentified source, the Angels want to retain Zack Greinke and will only consider exercising costly options on Haren and Santana if Greinke signs elsewhere.

Haren, 32, has a $15.5 million option for next year with a $3.5 million buyout. Santana, 29, has a $13 million option for next year with a $1 million buyout. Both pitchers are having disappointing seasons, but each is likely to attract heavy interest if available.

Either one would fill the Royals’ need for a workhorse starter. Haren is 12-11 with a 4.35 ERA and on pace to make at least 30 starts for a ninth straight year. Santana is 9-12 and 4.93 but on pace to reach 30 starts for the fourth time in five years.

Inherited runners

Maybe that Royals’ bullpen isn’t as air-tight as is generally believed; stat cruncher Bill Chuck of Billy-ball.com points out, through Tuesday, the Royals’ relief corps had allowed 32.4 percent of all inherited runners to score.

And since only the Boston bullpen had inherited more runners (286 to 284)…that’s a lot of runs. The Royals, in fact, led the AL in permitting 92 inherited runners to score – or roughly 10 percent of the league’s entire total.

The numbers are slightly kinder when viewed through a percentage prism: The Royals’ 32.4 failure rate was better than the Angels, who permitted 34.1 percent of inherited runners to score.

New York had the AL’s best rate at 22.3 percent. The league average is 29.3 percent.

Minor details

Outfielder Bubba Starling was the No. 3 prospect this season in the Appalachian League in top-20 rankings by Baseball America. Third baseman Patrick Leonard was ranked No. 16 and catcher Cameron Gallagher was No. 20.

All three played for Burlington and are currently taking part in the Instructional League at the Royals’ year-round complex in Surprise, Ariz.

Starling, 20, batted .275 with 10 homers and 33 RBIs in 53 games. He was the Royals’ first-round pick in 2011 and received a franchise-record $7.5 million signing bonus to reject a football scholarship to Nebraska.

“For Starling to deliver on his immense offensive potential,” Baseball America noted, “he’ll need to streamline his hitting mechanics and develop better pitch recognition.”

Leonard, 19, batted .251 with 14 homers and 46 RBIs in 62 games. He was the club’s fifth-round pick in 2011.

“Leonard offers profile power at third base,” Baseball America reported, “a quick bat and the controlled hitting approach and pitch recognition to continue hitting homers as he moves up.”

Gallagher, 19, batted .276 with three homers and 15 RBIs in 36 games but missed time because of various injuries. He was the Royals’ second-round pick in 2011.

“A simple swing and knack for barreling the ball suggest Gallagher will hit for average as he matures,” Baseball America reported, “and a high contact rate this season argues strongly for that case.”

Instructs update

Outfielder Jorge Bonifacio is off to a fast start in the Instructional League at four for eight with five RBIs through two games for Surprise, the combination Royals/Rangers team in the advanced league.

Bonifacio, 19, batted .282 with 10 homers and 61 RBIs this season in 105 games at Class A Kane County.

Looking back

It was 23 years ago Thursday – Sept. 27, 1989 – that Tom Gordon set a franchise record for rookies by winning his 17th game in an 8-3 victory at California. Gordon, then 21, improved to 17-9 after allowing two runs in six innings.

Gordon broke the Royals’ rookie record of 16 victories by Steve Busby in 1973 – but was a long time coming. He was 0-5 in his seven previous starts.

Gordon never again topped 12 victories in a 21-season career that saw him spend his later years as a closer. He was 79-71 with a 4.02 ERA in 274 games for the Royals over eight seasons from 1988-95.

Etc.

• Alex Gordon had two doubles in four at-bats, which raised his major-league-leading total to 51. It also matches Billy Butler’s 2009 total for the second-highest in franchise history. Hal McRae had 54 in 1977.

• Butler hiked his career-best RBI count to 103 with a two-out single in a three-run third inning.

• Irving Falu matched a career high with three hits, including a one-out double that ignited the three-run third inning. He raised his average to .379 (25 for 66) in 19 games.

• Jeff Francoeur’s homer in the fourth was his 14th of the season, which ties Eric Hosmer for third place on the club. Butler leads with 27, followed by Mike Moustakas with 20.

• The Royals had won nine straight starts by Jeremy Guthrie before Wednesday’s loss. He was 4-0 with five no-decisions in that span.