Part of the credit goes to the inevitable growth spurt most teenagers go through. But for all the promise Stephenson's 6-foot-2, 180-pound frame represents, it wouldn't mean much without his spotless attendance record at Gamespeed.
"I think that's been huge, doing that," said Stephenson, the 25th overall prospect in the Draft, according to Baseball America. "It's been one of the biggest things to help me, as far as strengthening and agility and everything."
Almost everybody at Alhambra knew about Stephenson's big night when he showed up to school on Tuesday.
"It was kind of crazy," he said. "It was fun, though."
He admitted he felt a little bit like a celebrity, although his new status at school was not by his own volition. As evidenced by a conference call with Reds reporters on Tuesday night, Stephenson's responses to questions rarely lasted more than a sentence.
On his senior year at Alhambra, where he threw back-to-back no-hitters: "I thought it was a pretty good season. I was pretty happy with it." On realizing he had been drafted by the Reds: "I really wasn't expecting that." On whether he has an agent: "I don't really want to talk about that."
Thigpen said that's just Stephenson's personality.
"He's really quiet," he said. "A lot of kids with his talent have a lot of bravado. With him, you wouldn't know it."
Thigpen said he heard plenty about Stephenson's highlights -- just not from Stephenson. Other kids he trained would ask him if he had heard about Stephenson, if he knew the "laser-focus" kid with a fastball sitting in the low-to-mid 90s.
That's not to say Thigpen and Stephenson weren't talking. In fact, the pitcher would talk a lot, but mostly they were chatting about tweaking his mechanics.
Thigpen, who also trained 2002 Reds first-round pick Chris Gruler, said Stephenson's level of focus was uncanny for a high school player. Each week during the season, the two would meet and Stephenson recalled minute details about his latest start: how many pitches he had thrown, how his torque was, what parts of his body felt tight.
Just where Stephenson will bring that level of maturity -- be it Reds rookie ball after signing a contract or the University of Washington, where he signed his letter of intent -- remains up in the air. Stephenson admitted neither choice is a bad one, but he didn't really have a timetable for making his decision. The signing deadline is Aug. 15.
Either way, Stephenson should still have plenty of time to grow. Thigpen expects Stephenson could add an extra 10 pounds to his frame, if he is handled the right way.
"He's intense, so he's going to give you all he's got," he said. "That's good, obviously, but it's got to be harnessed properly."
In a way, Thigpen said, Stephenson is a trainer's dream come true. But don't expect him to skip a session -- or talk too much about it later.
Live coverage of the 2011 First-Year Player Draft resumes at noon ET on Wednesday on MLB.com, where fans will receive exclusive coverage of Day 3, featuring a live pick-by-pick stream, expert commentary and Draft Tracker, a live interactive application that includes a searchable database of every Draft-eligible player. You can also keep up to date at Draft Central
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