What to know ahead of Giants prospect Kyle Harrison's MLB debut

What to know ahead of Giants prospect Kyle Harrison's MLB debut originally appeared on NBC Sports Bay Area

Kyle Harrison tried to keep a level head this spring, even though he was in big league camp and potentially just a few weeks from accomplishing a lifelong dream.

As he talked about his future one day, Harrison pointed out that he wouldn't feel slighted if the Giants decided they didn't need him in the rotation in 2023. That would mean, Harrison said, that the veteran starters were having a strong season and the rest of the team was in a really good place.

The Giants are, in fact, in the playoff race, and pitching is really the only reason they're still alive after a couple months of offensive struggles. But it hasn't quite gone as planned.

The rotation went from seven deep to two, with Logan Webb and Alex Cobb being the only regular starters. The Giants were able to cobble together bullpen games for a while, and do it very successfully, but cracks are starting to show.

The staff hoped Harrison would be a luxury addition at some point. They now need him to pitch well, and they're turning to him after losing for the 11th time in the last 15 games. The good news, at least internally, is that the Giants are very confident that the left-hander is ready to contribute, not just fill in. After an ugly 10-4 loss to the Philadelphia Phillies, manager Gabe Kapler reiterated that he's excited to watch Harrison attack the challenge.

"I have a lot of confidence in Kyle," Kapler told reporters in Philadelphia. "We all have a lot of confidence in Kyle."

Harrison's debut will come in a big spot, but it's one he's been preparing for since being taken by his hometown team in 2020.

Here's what you need to know about the top pitching prospect who will make the most highly anticipated start by a Giants prospect in over a decade:

Why now?

The Giants actually wanted to call Harrison up in July to see how he looked before finalizing their deadline plans, but a strained hamstring kept that from happening. Once the lefty got healthy, president of baseball operations Farhan Zaidi said it was "start to start" in terms of a promotion. Over his last two starts, Harrison struck out 11 and walked none in 7 1/3 innings, clearing the final hurdle to the big leagues.

The staff has been waiting all year for better command, and Harrison threw 44 of 60 pitches for strikes last week. It became clear after that appearance that a call-up was imminent, and Ross Stripling's injury means there's a real need at the big league level, too. The Giants were able to get by with three "bullpen games" in the rotation because Stripling was serving as a No. 3 starter who sometimes did that work out of the bullpen. But without Stripling, they're getting short on depth. They've been waiting for a time when Harrison felt like the right option and it's here.

"The last couple of outings I think he's taken some real steps forward," Kapler said Sunday. "We think he's ready to come up and help us win baseball games. That's the most important thing."

Wait, isn't this a tough environment for a debut?

In a perfect world, the Giants would have found a softer landing spot and allowed Harrison to debut a few miles from home, in front of a supportive crowd at Oracle Park, and against a team with a less imposing lineup. The Phillies lead the wild-card race, rank fifth in the majors in runs in the second half, play in a hitter-friendly ballpark and might have the most rabid fan base in the game. Harrison is going to be hearing from them as he warms up in the bullpen, which is uncomfortably close to the fans.

The 22-year-old is mature beyond his years, though, and the Giants have never worried about the mental part of his game. And the on-field matchup isn't actually the worst, especially given that the Phillies series is sandwiched between two against the Braves, who absolutely demolish left-handed pitching.

The Phillies rank 15th in the league in wRC+ against left-handed pitching and have the fourth-highest strikeout percentage, which should be helpful to a prospect who averaged 14.6 K/9 in the minors. Harrison also walked a lot of guys in the minors, but the Phillies are 24th in walk rate against lefties.

It's a lineup filled with big names, but Bryce Harper, Kyle Schwarber and Bryson Stott bat left-handed and are all close to league-average hitters against lefties. Nick Castellanos (141 wRC+ against lefties), Alec Bohm (139) and J.T. Realmuto (121) will be the ones Harrison has to be careful with.

"You might say that lefties give you a better shot," Kapler said. "I don't want to focus too much on that because this is really about Kyle earning the opportunity, hanging in there, fighting through a challenging season in some ways, but a really good development season in others. And he's just ready for the opportunity."

What were those challenges?

Aside from the poorly timed injury, it was mostly just a constant search for more consistent strike-throwing at a time when the Giants also had Harrison on a strict pitch count. Between those two factors, Harrison has completed five innings just once this season, and he has gotten through four full innings only five times.

The Giants never wavered in their belief, though. They actually might have gotten higher on Harrison, with team officials raving about the way he handled adversity in the spring and early in the year. Harrison was very self-aware throughout the process.

"It's really just trying to figure out what's going to get you ready for the big leagues," he said in June. "I think that's the biggest thing for me, and once I figure that out and I feel fully prepared, then I think it's a go. But at this point, I think we've got some things to work on and we're just going to keep working on it and keep getting after it."

What's he going to throw at the Phillies?

When he was drafted Harrison was often compared to Chris Sale, and while he's not as funky as the Red Sox lefty, he does hide the ball very well. He'll reach the big leagues as a four-pitch guy, with one of them being a recent addition.

Harrison's fastball sits in the mid 90s and will usually top out around 97 mph, and it has tremendous late life. He dominates hitters at the top of the zone, and the Giants believed one of his biggest issues in Triple-A was the automatic strike zone, which turned a lot of his top-rail fastballs into balls. It's reasonable to expect that Patrick Bailey will frame many of them into strikes in the big leagues.

"It was tough," Harrison told reporters at Citizens Bank Park. "It was pretty tight for pitchers, for sure. The strike zone for me felt pretty low. [Up high] is kinda where I love to pitch."

Harrison rose to Triple-A with a good slider and a changeup that he'll flash a few times per outing, but earlier this year he added a second breaking ball. The big sweeper is his traditional slider and is a weapon with two strikes, but he worked with director of pitching Brian Bannister and Triple-A pitching coach Garvin Alston to develop a firmer slider -- essentially a cutter -- which helps him get in the zone more often and record quicker outs.

"I think the fastball command has come along and it's been going good. I think I'm past the point of the fastball command (being an issue)," he said on the "Giants Talk" podcast in June. "Now it's figuring out how to throw that new slider that I'm throwing, the new gyro slider, how to land that more consistently to get me back in counts and just establishing the sweeper off of that. It's just trying to see what plays and figure out ways to sequence. That's the next step."

On Aug. 10, Harrison threw the sweeper 50 percent of the time and landed it for strikes about 80 percent of the time. Last week, he threw the sweeper 22 times and the cutter nine times, reaching 90 mph with the latter pitch.

The slower slider will make hitters look foolish at times and lead the highlight reels. But it's the mastery of the new cutter -- he threw all nine for strikes last week -- that will allow Harrison to reach his ceiling.

So, what are the expectations?

Harrison threw 38 pitches on Aug. 10 and then 60 last week. He should have about 75 in him Tuesday night, so it likely won't be a long start, and the Giants would probably be pretty thrilled if he could cruise through the lineup once and then get past Harper a second time before handing the ball over to the bullpen.

Harrison is here as a starter, but for now, he's not all that different than Stripling, Jakob Junis and the other bulk guys. Until the Giants can get his pitch count up, they'll likely piggyback him with other bulk arms. Because of the occasional command issues and all the strikeouts, Harrison has longer innings than most, so it'll take some time before he's counted on for five to six innings per night.

He has the stuff to be dominant in shorter bursts, though, and that's the hope as he finally makes his debut. No matter how things go, this is a moment that the organization will enjoy and fans should as well.

Harrison is the best starting pitcher the Giants have developed since Madison Bumgarner, and the expectation is that he'll team up with Logan Webb the rest of the decade to form an imposing one-two punch. The Giants are hopeful that years from now, we're all looking back at this night as one that helped the organization take the next step.

Download and follow the Giants Talk Podcast