Under the Radar Prospects: Raffi Vizcaino
A long climb has left the power-armed reliever on the cusp of success
Happy Monday everybody! There’s snow on the ground, the Super Bowl is over, and spring training maybe just a week away! Let’s hit the field and continue digging into the careers of some of the smaller prospect stories in the Giants’ system. I’ve been doing a little crowd-sourcing, and a few people have asked about Raffi Vizcaino, who does have a fascinating history in the Giants’ system. So let’s start the week by checking out this long-time Giants’ farmhand.
You really have to jump into the Wayback Machine to trace Vizcaino’s history in the organization, as it goes back almost a decade. The Giants originally signed Vizcaino as a part of their 2012 J2 class — a signing class that was dominated by the $1.3 million they gave to the ill-fated Gustavo Cabrera. Their second highest signing of that class was a 3b named Nathanael Javier, who trained at the Dominican camp of Bausilio Vizcaino. Javier was almost immediately hit with a PED suspension and his career would never get out of rookie league level. But perhaps scouting and signing him benefited the Giants regardless, since at the very end of that signing period, they signed Vizcaino’s nephew Raffi to a $200,000 deal as well. Somewhat surprisingly, it was Raffi who would have the longest Giants’ career in the organization of the 2012 group. In fact, at this point Vizcaino is the longest serving prospect in the Giants system. The only prospect who was in the Giants’ minor league system when Vizcaino started his career who is still a player in the organization is Reyes Moronta. Even Tyler Rogers was not yet a glimmer in the org’s eye when Vizcaino made his playing debut on June 2, 2013.
The team that Vizcaino debuted with — the 2013 DSL Giants — also included a 20-year-old Luis Castillo and current Yankees’ pitcher Jonathan Loaisiga (whom the Giants would ultimately release when injuries kept him off the field for the next three seasons). Vizcaino had a reasonably good debut as a 17-year-old, making 11 starts for the team, posting a 3.80 ERA (a tad high for the run- and defense-challenged league, but certainly not bad), striking out 41 and walking 17 over 47 IP. The control was an issue (hold that thought), but that’s hardly unusual for a 17-year-old in the DSL.
In 2014, he was kept in the Dominican to build on his strong debut, but this time the Giants decided to look at his burgeoning power arm (he was throwing around the low 90s at this point) in a closer role. In his second game of the season, he faced three batters, struck out two of them, and collected his first professional save. It would be the last time he threw that year.
I’ve never seen anywhere definitively what kept Vizcaino off the field in 2014 or whether surgery was involved. But it does seem certain that it was a medical issue — unlike many other young Dominican pitchers, Vizcaino never had the issue of needing to add weight and strength. Regardless, his second year was over almost before it started, with just 2 professional innings added to the back of his baseball card. He’d return in 2015 for a third shot at the DSL, and once again his role would shift, as he returned to the starting rotation.
I’ve written several times about the Giants 2015 DSL Championship team, often in the context of the team’s offensive lineup (Sandro Fabian, in particular). But it was the splendid pitching staff that was the strength of that team and Vizcaino was right in the middle of it. The starting rotation (which also included Melvin Adon, as well as Sandro Cabrera, Victor Concepcion, and Norwith Gudino) anchored a staff that paced the league in strikeouts and finished fourth in team ERA. Vizcaino was in the middle of both stats, posting a 2.50 ERA and finishing 8th in the league with 73 strikeouts. He would ultimately take part in the clinching games of both the semi-finals and the championship. He threw the final four innings of the title game, picking up the clinching save.
After three years in the Dominican complex — and having come back strong from injury — it was time to move Vizcaino a little more aggressively. The following year, along with several of his rotation-mates, Vizcaino was skipped over the AZL and pushed directly to short-season Salem-Keizer. And, as was true of Concepcion and Adon, so too for Vizcaino it proved a tough skip-level for him. With the Volcanoes, his ERA would jump up to 4.60 and the walks — which had always been a concern for him — ballooned up to 4.4 per 9 innings.
Still, there was an intriguing ability to miss bats with a low 90s fastball, a terrific change and a spiked slider. He ended the year getting a late callup and a couple of starts in Augusta, and it looked like he was ready for a full season assignment. I saw him the next spring and the entire arsenal looked fantastic. In fact, I was standing next to Conner Penfold when he shot this great footage of Raffi that spring at the A’s complex.
Oddly, he went unassigned out of spring complex that year and again it’s something of an unexplained absence to the best of my knowledge. Probably a bout of ill-timed arm soreness but, once again, he was set back a bit. He finally showed up in Augusta in early June, pitching out of the bullpen while rounding back into shape. When he finally got to make his first start of the year, it was a memorable one as he immediately threw 6 hitless innings with 9 Ks.
That explosive start teased a breakout season. Instead, Vizcaino produced a generally unimpressive season with more downs than ups. He’d allow at least three runs in each of his next eight starts, included blow ups of 9 and 6 runs in back-to-back starts in July. Even the strikeouts would wax and wane — though he did produce a high of 11 Ks in his penultimate start of the year. It was still a powerful and intriguing arm, but the whole package was just too inconsistent — the stuff, the command, it all just wavered too much, flashing dominance for a moment before falling back into long scuffling stretches.
By 2018 in San Jose, the flashes of dominance came fewer and further apart. He walked 52 batters in 79.1 IP, surrendered 11 homers, had a WHIP of over 1.5, and, once again, an ERA in the high 4.00s. There were still some big strikeout games, including 17 Ks over 11 innings in a two game stretch in May. Still, six seasons into his pro career, the trend lines were not pointing upwards for Raffi Vizcaino.
The solution, as is so often the case, came in a move to the bullpen. The Giants returned Vizcaino to San Jose in 2019, but for the first time since 2014, they wanted to take a look at him at the end of the game, not at the beginning. And the results were immediately impressive.

Pushed to the pen, his velocity took a huge leap up, pressing close to triple digits. And with the increased heat, his excellent secondaries dominated A-ball hitters. While the control was still a work in progress, there was no denying the impressiveness of his 30 K to 8 BB ratio in just 16 innings. That got him a quick promotion to AA, where the advanced hitters were able to take a little better advantage of his wavering command. While he still showed powerful swing and miss stuff, striking out 44 AA hitters in 46.2 innings, he also walked 27, helping push his opponents OBP up to .342.
It all adds up to an enticing, though frequently frustrating, package: a power arm capable of hitting 98-99, combined with a deadly change and tight breaker that can really fool hitters when he commands it. But it all has a tendency to play down because of below-average control. The appeal is obvious — how far removed is Vizcaino from putting together enough control to pop into a major league bullpen? How different is he from having a Jose Mijares-type career (Mijares posted a BB9 of 5.00 in his minor league time)? It’s all there, it just needs to be refined slightly. On the other hand, how many arms in AA baseball can we say the same about? Even in the Giants’ system Sam Wolff stands out as an obvious comp. The guys who look like they’re good enough, but fall just enough below average at one thing to hold them back? It’s the unofficial AA motto. So close but yet…
The Giants obviously want to see those last steps from Vizcaino. They offered him a non-roster invite in 2020 and, when he became a minor league free agent after the lost season, they immediately signed him back and extended an invite for 2021 as well. Every year, we pour over the list of minor league signings (like Sam Long and Dominic Leone and Zack Littell and Jay Jackson and James Sherfy and…and…and) and wonder “which of these guys is going to pop onto the radar in spring?” And, it’s important to remember that if Raffi Vizcaino were a free agent signing from some other organization, we’d look at him in this same manner — “wow! big arm! and look at that change drop off the table!” We’d squint our eyes and think, “yeah with just a tiny little adjustment that could all really be something!” And it could! It really could! The control is an issue — and given the recent trades of Sam Coonrod and Shaun Anderson this doesn’t appear to be an organization with a lot of patience for power arms with control problems. The body will always be “high maintenance,” and demand he stay on top of his conditioning. Those things describe a lot of career minor leaguers. But they also are the preliminary descriptions of late bloomers, or guys who suddenly pop up at some point and take those final steps, if only for a time.
There’s one other little wrinkle in the story as we begin heightening our anticipation for seeing pitchers and catchers report. As with Melvin Adon, Vizcaino’s final pitch this winter in the LIDOM (Dominican Winter League) may have caused some damage as he appeared to leave that last game in discomfort.

Hopefully, that was minor and didn’t hamper the rest of his off-season preparations. With any luck, we’ll see Vizcaino report with the rest of the pitchers and begin the process of trying to stand out from so many other arms.
Will it happen for Vizcaino? Eight years in and the answer is still: “Check Back Later.” Or perhaps better said: any outcome is equally believable for a talented and flawed pitcher like him. But he’s worked his way up to the point where the opportunities can come like lightning. He’ll be seen by a major league staff that is looking for results and will respond swiftly if they see them.
Good luck, Raffi! We’re rooting for you!
More “Under the Radar” Prospects:
Some of you have asked for an “Under the Radar” piece on Joey Marciano, as well, but, until I get around to that, here’s an older piece I wrote about Joey’s comeback that might suit the same purpose.
And, as always, I’m happy to take requests!
Sam Long?