PHOENIX -- It took Junior Guerra five years to master a split-fingered fastball, the pitch that carried him from professional leagues in Italy and Spain all the way to the Major Leagues.
Hall of Famer Rollie Fingers learned his in 2 1/2 weeks.
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Fingers, the mustachioed reliever who won the 1981 American League Cy Young Award in the first of his five years with the Brewers, was on hand at Maryvale Baseball Park on Wednesday to sign autographs, with proceeds benefiting the Fergie Jenkins Foundation. He spent some time chatting with Brewers manager Craig Counsell about the "split," a popular pitch in these parts because it lifted Guerra to the top of Milwaukee's starting rotation last season as a 31-year-old rookie.
"I didn't throw the pitch for nine seasons in Oakland, but I went into Spring Training with San Diego and started to fool around with it," Fingers said. "At first, I was all over the place.

"I had smaller hands, so to get it in there I had to stick a ball between my fingers and tape them up. I walked around like that. I had to stretch those tendons enough to get the ball in there."
Fingers tried it out in a handful of Spring Training games and produced off-balance swings, so he began working the pitch into his repertoire and it became a go-to changeup. Eventually, Fingers felt comfortable throwing it in any count.
That was in the late 1970s and early '80s, early in the splitter's heyday. Bruce Sutter of the Cardinals, the Brewers' foe in the 1982 World Series, rode it to the Hall of Fame. Fingers remembers Jack Morris' as the nastiest. Roger Clemens, Randy Johnson and David Cone used it to remain dominant pitchers late into their careers as well.
For Guerra, the pitch got him to the big leagues.
"I have no idea where I would be without it," Guerra said last year.

Guerra, who will make his second spring start Friday, was out of organized baseball from 2009-14 following a Minor League drug suspension. He was pitching in Venezuela when Giants reliever Jean Machi showed Guerra his grip. Over the ensuing years, in such places as Venezuela, Mexico, Europe and Wichita, Kan., Guerra made it his own.
Some believe the splitter fastball fell out of favor because it puts additional stress on a pitcher's arm and costs him fastball velocity. To the contrary, Fingers said.
"I think it took stress off my arm because I wasn't throwing it as hard," Fingers said. "I was throwing it as more of a changeup. I was throwing it where I kept the same arm speed as my fastball, but the ball would slip out between my fingers and go out about 10 mph slower."
Guerra's acted similarly last season, when he posted a 2.81 ERA in 20 starts. According to Pitch/FX data from Brooks Baseball, the average release speed of his four-seam fastball was 94.3 mph and touched 97.3 mph. His splitter averaged 86 mph and reached 90.6 mph.
The pitch is effective because of its extraordinarily slow spin rate, which is a positive trait for pitches that dive. Statcast™ registered 252 splitters from Guerra in 2016, with an average spin rate of 1,013 revolutions per minute that ranked third-lowest among the 25 pitchers who threw the pitch at least 100 times. Mike Pelfrey of the Mets threw the splitter that spun most slowly, at an average of 932 rpm.
"It doesn't make any difference how you do it -- circle change, palm ball, whatever," Fingers said. "As long as you can throw something with the same arm speed as your fastball that goes in slower, you're going to mess hitters up."