"I used it," White said. "It wasn't very good, but I used it."
The development of the slider played a role in White's rapid progress and eventual promotion to Cleveland's rotation last week. The Indians wanted the right-hander to concentrate on upgrading that offering, giving him another weapon to use once he reached the big leagues.
That is precisely what the pitch has become.
"It came along at the end of the year," said White, referring to his first professional season in 2010. "It was a decent pitch, but it was nothing like it is now. It's a completely different pitch. It's actually something I can use in big situations.
"I can throw it early in counts for strikes. I can throw it when I'm behind in the count. I can throw it when I'm ahead in the count as a chase pitch. It's really become a weapon for me."
During his Major League debut on Saturday, the 22-year-old White relied heavily on his two-seam sinking fastball and his slider in a six-inning outing against the Tigers. He estimated that he used his splitter -- one of his best pitches -- only four or five times against Detroit.
When the Indians selected White in the first round (15th overall) in the 2009 First-Year Player Draft, he did not throw a slider. Last year, while using it sparingly, he took home the club's Minor League Pitcher of the Year Award by going 10-10 with a 2.45 ERA between stints at Class A Kinston and Double-A Akron.
Now, with an improved and reliable slider at his disposal, White understands why Cleveland wanted him to work so hard on the pitch.
"Absolutely," White said. "Early on, I was able to get guys out with fastballs. Even in Triple-A, just fastballs, you're not going to get guys out. It's really taught me how to pitch, and pitch in the strike zone with three or four different pitches."