CHICAGO -- Luke Little heard a few gasps in the gym around the portable mound he was on, but the left-hander was not done working through his bullpen session. He figured he did something right -- probably even hit triple digits -- but the specifics would have to wait.

"I didn't know what I did," Little said. "I finished my bullpen and found out what I had hit."

105 mph.

Video of that practice fastball at the Showcase Baseball Academy was posted on Twitter by Jake Robbins (a coach and former Cleveland pitcher) on May 8. The likes and retweets and reactions began pouring in. Little replied to the post with a photo of himself holding up the baseball with "5 oz" written on it, along with a smiley face, in case anyone doubted the sphere's weight.

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Between that initial post and Little tweeting it on his own page -- with the comment "Another PR #nofluke" -- the video has racked up nearly 1 million views to date. Little was already on scouts' radar, but now he was on the baseball world's radar. That made him an interesting prospect as the days ticked down to the MLB Draft.

"I think the upside is obvious," Cubs vice president of scouting Dan Kantrovitz said. "It's been well documented he's been up to 105 recently, which is not something that you see every day."

And it was not something that happened overnight for the 6-foot-8 Little, who was selected by the Cubs in the fourth round last week.

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What happened in that viral video was not a fluke but the result of years of work and growth. As a freshman and sophomore at East Mecklenburg High School in North Carolina, Little threw a fastball that was still in the 70s on the radar gun. He was still growing, adding strength and working with instructors -- most recently Pat Robles, who is currently a Phillies Minor League coach -- on body movements, mechanics and velocity training.

"It was just years and years of changes," Little said. "It's come a long way, and I appreciate everyone that's helped me get here."

Little knows the work is just getting started with the Cubs, too.

"He's going to be somebody that we're going to, I think, really just leverage the resources and instructors and technology in our player development operation," Kantrovitz said. "Whether that's in pitch design, whether that's in refining his mechanics or getting consistency in release point, he definitely has some work to do."

That makes it clear that the 19-year-old is kind of a project, but one with tremendous potential.

Little has already had a taste of what's in store with the Cubs, dating back to their Zoom call prior to the Draft. Staffers from player development and research and development participated, and the group broke down specific moments on video. Little shared his thought process, and the Cubs' group offered feedback.

"We actually went through a whole process," Little said. "They kind of wanted me to analyze some at-bats and kind of like let them know what was going on through the at-bats and what I was thinking through what was going through my head. It was very impressive.

"They like to use a lot of software, which will help me develop a lot. I think I have a really good chance at developing into a pretty good starter or reliever, however they want to use me. ... I'm so excited for it. It's going to be a lot of help with helping develop me as a pitcher. All the data's going to help so much with it. It's going to be astronomically better than college."

During Little's abbreviated 2020 season at San Jacinto College, his fastball was in the 97-98 mph range during his relief outings. He would couple that with a slider, and mix in a developing changeup and curveball when used as a starter. In two years in JUCO ball, Little piled up 86 strikeouts in 44 1/3 innings.

The Cubs were one of the teams on his radar going into the Draft, but that did not lessen the excitement when the call came.

"It was exhilarating," he said.

Kind of like a 105-mph fastball.

Little was asked if he has a message for anyone who claims that now-famous heater was a fluke or the result of a wonky radar gun reading.

"I mean, no one will ever know," he said. "Innocent until proven guilty."