CHICAGO -- Lucas Giolito was not the pitcher he could be -- or more importantly, should be -- during his short Major League stint with the Nationals last season.
MLBPipeline.com's No. 11 prospect per the 2017 Top 100 rankings fanned only 11 in 21 1/3 innings for the Nationals, giving him a 10.9 percent strikeout rate that was the 12th-lowest of the 511 pitchers with at least 20 innings. That number stands as a stark contrast to the 397 strikeouts Giolito recorded over 369 Minor League innings.
According to Statcast™, Giolito's fastball sits at the core of those struggles. Opposing big league hitters posted a split of .349/.446/.730 off that pitch, with his spin rate of 2,061 rpm falling below the Major League average of 2,261 rpm.
A lower spin rate can produce sink and grounders, and Giolito throws a sinker as well as a four-seamer. But the higher spin is correlated with swinging strikes, and the 6-foot-6 right-hander considers himself a strikeout pitcher.
"It's enjoyable to strike people out, that's for sure," Giolito said during last weekend's SoxFest. "It's always good to be able to put guys away. I know I have the stuff to do that. I have to continue to hone it in.
"I'd say the lower spin rate was probably because I wasn't extending as much. I was really flying open a lot last year. I've been working super hard to get back to basics with my mechanics this offseason and put it all together. I feel like the ball is coming out of my hands much better right now."

Studying specific statistical trends such as spin rate is important enough to the White Sox that they hired Matt Koenig as director of baseball analytics to focus on Statcast™ and Trackman.
It's becoming prevalent in the scouting circles as well because more of the information makes its way to the colleges, major summer tournaments and even some of the high school stuff.
Fastball issues for Giolito centered on changes in mechanics implemented when he arrived in Washington. Giolito, 22, blames himself for trying to be something he really wasn't.
"This year it's kind of like a clean slate," Giolito said. "It's even a new team. I'm able to, like I said before, kind of get back to basics in my mechanics. Go back to what made me successful and continue to do that so I can continue to be successful.
"I was trying to make adjustments that I thought might have been helpful, might have made me more consistent with my mechanics, or might have gotten more out of my legs or arm ... I was trying to juggle it, and then I developed some really bad habits."
Those habits seem to be past history, as Giolito has felt great since he started throwing again. He earned rave reviews from pitching coach Don Cooper during a side session Friday.
"We've got to create a little more angle, a little bit more down angle to the fastball," White Sox scouting director Nick Hostetler said. "When you do that, it essentially causes the hitter to have to change his launch path in his bat. You put all these things together and it ends up building up to a point where he becomes, he realizes his deficiencies. Our coaching staff does, as well as us in the office, and we get information to him to fix that."
"The ball is going to be coming out of my hand different this year than it was in the big leagues last year," Giolito said. "I saw I was throwing 90, 91, 92, and that's not going to be happening. I'm not interested in being that type of pitcher. I can put power behind the ball. I can throw inside/outside. I can throw the curveball/changeup. I'm just going to continue to work on all that stuff and put it all together so I can go and win games in the big leagues. It's what I really want to do."