PHILADELPHIA -- The Giants now use many of the same tracking methods in the minors as they do in the big leagues, so when it comes to evaluating their top prospects, they have every piece of necessary data. They have spin rates and exit velocities and incredibly detailed splits, but all they really needed to know that left-hander Kyle Harrison was ready for the next challenge was pretty basic math.
"If he punches out eight in his last start and his punchout rate goes down to 50 percent, it's pretty smoking-gun evidence that he's too good for the level and we wanted to reward him with a promotion," general manager Scott Harris said on Monday's Giants Talk podcast.
That's not hyperbole, either. In his last start for High-A Eugene, Harrison threw five scoreless innings and struck out eight, giving him 59 strikeouts over 29 innings. That was overwhelming evidence that the 20-year-old lefty was ready for the next step, and it might not be long before he's ready for yet another one.
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Harrison made his Double-A debut on Friday and put up what has now become a familiar line: 5 2/3 innings, two earned runs, six hits, one walk, nine strikeouts. It was the fifth time in eight starts this season that he struck out at least nine, and -- perhaps just as importantly -- the fifth time he walked one or fewer.
Overall, Harrison has a 1.82 ERA in 34 2/3 innings. The Giants have been cautious with promotions for their best prospects, but Harrison proved he was ready by allowing just five earned runs in seven High-A starts and piling up all those strikeouts. As Harris said, "Kyle forced our hand here."
"He was so dominant in High-A in Eugene that he demonstrated he was too good for the level," Harris said. "That's a standard that we want to apply up and down our minor league system. We want players to demonstrate to us that they are too good for the level and they need a challenge above the current level that they're playing at."
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Harrison is the highest-profile Giant to be promoted so far this season, and that doesn't surprise team officials who raved about him early in minor league camp. Harrison showed up for his second full professional season in much better shape. While meeting with beat reporters in March, he explained how he put on too much weight last year but adjusted in the offseason.
Figuring out the right way to grow can be tricky for a lanky teenager, particularly one like Harrison who saw velocity gains as he became a professional and bulked up a bit. But there's a balance.
"In kind of the middle of (last) season I would say I was gaining some weight and not feeling as explosive off the mound," Harrison said. "I really took this offseason to really, really work on my diet and work hard. I came back and I thought a lot of people were impressed with how I looked and I was impressed with how I felt, and that's the most important thing."
If Harrison felt off at all last season, it didn't show in the box scores. He struck out 157 across 98 2/3 innings with a 3.19 ERA, winning Low-A West Pitcher of the Year honors for the San Jose Giants. The former De La Salle star got to start his professional career close to home, in large part because of a gamble the Giants took during the five-round 2020 draft.
The Giants went under slot -- often well under -- with five of their six selections other than Harrison, who was taken in the third round. Harrison was viewed as having a strong commitment to UCLA, but the Giants met the asking price, giving him a bonus of $2.5 million that was the value for a late first-rounder.
As he looked back on that decision this spring, Harrison said it was "very difficult" to pass up a chance to play for UCLA, but he and his parents felt it was the best move for his development. "I couldn't be happier with my decision," he said.
Harrison did not get to pitch in 2020 and said it was difficult to watch friends go off to college as he was sidelined. He spent that time in the weight room, and last year he finally got to start chasing his dream.
"I remember walking in on the first day and going, 'These are men in here. This is crazy," Harrison said, laughing.
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He was just 19 when he debuted in San Jose, but he made it look easy, showing off the three-pitch mix that has made him the organization's best pitching prospect since a young Madison Bumgarner more than a decade ago. The fastball was in the low 90s in high school but now ticks up to 97 mph, and the slider is a plus pitch already. Harrison, currently ranked as the minors' 64th best prospect by Baseball America, said his focus this season is on developing his changeup and limiting his arm-side misses.
The early results couldn't be more promising. After Harrison was sent to Double-A, Harris said his development has been "one of the highlights of the year" for the Giants.
"It's especially energizing knowing he's a Bay Area kid," Harris said. "Watching him pitch, what sticks out to me is he just has a totally overwhelming mix. He has an overpowering fastball (that) touches the upper 90s and it plays in all parts of the zone but it especially plays up in the zone, and he pairs that with two different secondary pitches. He has a wipeout slider that performs against lefties and righties, and he's also added a developing changeup that has shown that it can miss bats in the zone.
"Those three pitches helped him get off to such an overpowering, dominant start in Eugene."