SF Giants pitching prospects week in review (8/22-8/28)

Make sure to revisit our weekly SF Giants prospect rundowns to keep up with each of the organization’s minor-league affiliates. If you do not feel well acclimated to the prospects throughout the farm system, you might want to revisit our prospect week articles that detailed the system from the top prospects to lower-level fringes. If you’re just interested in the biggest names, then the preseason SF Giants top 31 prospects list is the one-stop-shop for you.

SF Giants Prospects Weekly Rundown: Triple-A

Notable Performers

Kervin Castro: 1 G, 2 IP, 1 H, 0 R, 1 BB, 3 K, 0.00 ERA
Camilo Doval: 2 G, 1.1 IP, 2 H, 0 R, 0 BB, 3 K, 0.00 ERA
Sean Hjelle: 1 G, 1 GS, 5 IP, 10 H, 5 R (5 ER), 3 BB, 2 K, 9.00 ERA

What a roll Kervin Castro is on this season for the River Cats. The 22-year old is pitching to the tune of 1.20 ERA in his last eight appearances with a 20 to 5 strikeout to walk ratio in 15 innings of work. There seems to be a pattern of work for Castro all season as he is pitching every fourth or fifth day and has pitched at least two innings of work in 10 of his last 13 appearances with a 2.08 ERA and has only allowed a .191 opponent’s batting average. While he is pitching very well, the next thing for Castro is pitching effectively with fewer days of rest.

After struggling for most of this season, Camilo Doval has found his groove this August with seven scoreless outings in both Sacramento and San Francisco. He has not allowed a walk in his last six outings and has a nice 69% strike rate over that stretch with 11 strikeouts in 6.1 innings of work. Hopefully, this is the start of things trending in the right direction for Doval.

Sean Hjelle‘s start to his Sacramento career has been rough. The 2018 second-rounder has a 6.23 ERA in his three starts for the River Cats with almost twice as many walks as strikeouts (9 walks vs. 5 strikeouts) in 17.1 innings. Upon watching his starts, Hjelle has a little problem throwing over the strike zone but is failing at executing his pitches and his stuff is getting timed by minor league veterans quickly. He’s nibbling instead of attacking hitters even though his mid-90s fastball velocity should be enough to get outs.

SF Giants Prospects Weekly Rundown: Double-A

Notable Performers

Michael Plassmeyer: 1 G, 1 GS, 0.2 IP, 6 H, 4 R (4 ER), 1 BB, 2 K, 54.00 ERA
Matt Frisbee: 1 G, 1 GS, 5 IP, 5 H, 3 R (3 ER), 1 HBP, 1 BB, 3 K, 5.40 ERA
Luis Amaya: 2 G, 4 IP, 3 H, 1 R (1 ER), 0 BB, 5 K, 2.25 ERA
Joey Marciano: 2 G, 3 IP, 1 H, 0 R, 0 BB, 1 K, 0.00 ERA

With Sean Hjelle promoted to Richmond and Caleb Kilian traded to the Cubs, there is a big void that exists at the top of the rotation for the Flying Squirrels that coaches hope Michael Plassmeyer can fill up. In his last three starts, however, Plassmeyer has been rocked for an 8.31 ERA in 13 innings of work. He struck out 18 hitters and only walked four but the big issue is the loud contact that he gave up with 21 hits and five home runs within the stretch. The left-hander now has a 4.73 ERA but is vastly split in his home-road splits with a 6.00 ERA on the road but a 2.06 ERA at home.

The Giants are also hopeful that returnee Matt Frisbee could fill up the void. His three starts since coming back are not particularly positive, however, with a 4.96 ERA. There is nothing particularly problematic with Frisbee’s peripherals as he is still throwing strikes at an above-average rate at 67%. The problem is the vast increase in terms of the loud contact that he gave up, particularly home runs.

A couple of left-handers were effective this week. Both Luis Amaya and Joey Marciano were lights out this week after struggling a bit the previous week. Amaya is on a roll in his last six outings with a 2.31 ERA in 11.2 innings pitched with a 16:3 strikeout to walk ratio. Marciano, on the other hand, has slightly fallen off the rails after a superb start to his 2021 season with a 4.91 ERA in his last 21 appearances and was a heavy victim of the BABIP gods with a .348 rate. Both Amaya and Marciano could see time in Sacramento next season.

SF Giants Prospects Weekly Rundown: High-A

Notable Performers

Ryan Murphy: 1 G, 1 GS, 5 IP, 3 H, 2 R (2 ER), 3 BB, 8 K, 3.60 ERA
Jasiel Herrera: 1 G, 4.2 IP, 2 H, 0 R, 0 BB, 8 K, 0.00 ERA
Aaron Phillips: 1 G, 1 GS, 1 W, 7 IP, 7 H, 3 R (3 ER), 1 BB, 6 K, 3.86 ERA
Blake Rivera: 1 G, 1 GS, 2 IP, 3 H, 3 R (2 ER), 1 BB, 1 K, 9.00 ERA

Ryan Murphy did not pitch his best game this week for the Emeralds, but if he is this effective when he is not at his absolute best then it’s a good sign of things to come. With 13 induced swings and misses against the Dust Devils, Murphy extended his active streak of inducing double-digit whiffs per start to 10 and he continues to lead the minors in strikeouts this season with 153. Murphy has a fantastic 1.65 ERA for Eugene.

Jasier Herrera was at his best last night with a dominant relief appearance following a short start from Kai-Wei Teng. After stopping the bleeding by inducing two crucial outs to stop the bleeding. He then pitched four dominant innings with only two harmless singles and a season-high eight strikeouts. Herrera is on a roll this month with a 1.46 ERA in 12.1 innings of work with a 17:2 strikeout to walk ratio.

In a rather surprising decision, the Giants brass decided to release Aaron Phillips a day after pitching a season-high matching seven innings of three-run baseball. Phillips has not had a good 2021 for the Emeralds with a 7.06 ERA and only 48 strikeouts in 72.2 innings pitched across 16 starts which is a sharp decline compared to his previous two full seasons where he logged triple-digit strikeout totals. It was surprising that they released him after a solid start. I am wishing the best for Phillips in his future endeavors.

A couple of pitchers got added to the Emeralds pitching staff following the release of Phillips. The first is Nick Morreale who pitched well at the start of the season before going down with an injury. The second is Blake Rivera where he is three months behind schedule after suffering a shoulder injury. The first start in High-A for Rivera was not pretty but it was nice to see him back. Reports from Arizona are that his swing-and-miss stuff is still there. He would be an interesting follow towards the end of the season.

SF Giants Prospects Weekly Rundown: Low-A

Notable Performers

Kyle Harrison: 1 G, 1 GS, 5 IP, 5 H, 1 R (1 ER), 1 BB, 9 K, 1.80 ERA
Nick Swiney: 1 G, 1 GS, 3 IP, 2 H, 0 R, 1 BB, 7 K, 0.00 ERA
Randy Rodriguez: 2 G, 1 W, 3 IP, 2 H, 0 R, 1 BB, 7 K, 0.00 ERA
Prelander Berroa: 2 G, 2 GS, 11 IP, 7 H, 6 R (5 ER), 1 HBP, 5 BB, 12 K, 4.09 ERA

Even though the Giants have looked after his pitch load in recent weeks, Kyle Harrison was as good as ever in his latest start with five innings of one-run ball and nine strikeouts. Known for generating a high whiff rate, Harrison has his best month ERA-wise in August with a 2.33 ERA and 33 strikeouts in just 19.1 innings pitched. The nine walks and six hit batters are however on-brand for Harrison’s sometimes erratic control, but he is generally in the strike zone more often than not.

Nick Swiney had another stellar start this week as he continues to pile up the innings after missing a good chunk of the season with a concussion. Swiney is on a 50-pitch limit but he is making up for the lost time. His latest start against Lake Elsinore was vintage Swiney as he got the Storm hitters off-balanced by junk balling them with curveball and changeups that drew out 11 swings and misses. The changeup consistently flashed plus while the control of his curveball was decent even though it flashed above-average. Due to how advanced Swiney is and how many reps he missed due to injury, there is a possibility that he will be pitching in the Arizona Fall League.

After being named the Low-A West Pitcher of the Week, the first San Jose reliever to win the award this season, Randy Rodriguez continued his stellar month with two more dominant outings this week. If Rodriguez made his final appearance of the month last night, it will cap off what was potentially one of the most dominant months I have seen from a reliever all season long, with 15.2 innings of shutout baseball allowing only nine hits with a 27:3 strikeout to walk ratio. He looks electric on the mound with great athleticism, lightning-quick arm speed, mid-90s fastball, and a hard slider. Rodriguez has a shot to win the Pitcher of the Month with his performance.

Prelander Berroa had a tough August with a 4.84 ERA but the most concerning thing is his strike-throwing having only thrown 58% of his pitches for strikes compared to July where he threw 64% of his pitches for strikes. He allowed 14 walks in 22.1 innings pitched. His latest start, however, was reminiscent of Berroa’s dominant July except for a home run he allowed on a hanging slider. Even though Berroa’s numbers looked rough this month, I like how he tried to use his slider as a chase pitch a bit more often.