Starting Pitcher Notes (May 9): Tanner Bibee, Luis Castillo, Trey Yesavage, and Spencer Strider.
Corbin Young examines a few starting pitchers from May 9, including Tanner Bibee, Luis Castillo, Trey Yesavage, and Spencer Strider.
Tanner Bibee, SP, Guardians
Cleveland Guardians’ starting pitcher Tanner Bibee elicited 20 whiffs on Saturday against the Twins. It’s the first time Bibee has had 20 whiffs since June 2024. Bibee elicited a 20.4% swinging-strike rate with a 39% ball rate on Friday.
🪙Bibee increased his changeup usage to left-handed hitters (34%) on Saturday, up from 28.6% (2026). That coincided with Bibee throwing fewer curveballs (4%), down from 12% (2026) before Saturday. Bibee’s changeup elicited a 23.1% swinging-strike rate on Saturday, with most of his whiffs coming low and outside from left-handed hitters.
✂️Bibee continued to pump cutters against righties, throwing them 42% of the time on Saturday. That’s up from 34% in 2026 before Friday and 27.2% (2025) against right-handed hitters. Bibee’s cutter added 1-2 inches of downward movement and horizontal sweep on Friday, like a gyro-like slider.
✍️The cutter has been successful for weak contact (76.7 mph average EV) and whiffs. That’s evident by Bibee’s cutter swinging-strike rate (19% on Saturday), though righties have been crushing them (.397 wOBA, .401 xwOBA) before Saturday. Theoretically, Bibee’s cutter movement profile should generate weak contact and whiffs, as a pitch he tends to locate low/away from right-handed hitters.
Hopefully, this is a launching point for Bibee to find more consistency.
Luis Castillo, SP, Mariners
Seattle Mariners’ starting pitcher Luis Castillo generated a season-high 18 whiffs on Saturday, leading to a 21.4% swinging-strike rate with a 30% ball rate against the White Sox. That’s significantly better than Castillo’s career ball rate (35%), yet an 11% swinging-strike rate before Saturday.
⏩Castillo was peppering the four-seamers in the upper parts of the zone, adding 1 inch of induced vertical break. Castillo’s four-seam elicited a 27% swinging-strike rate on Saturday, compared to 11-13% over the past two seasons. At Castillo’s peak, his four-seam generated a 15-16% swinging-strike rate. That’s an optimal approach to repeat.
🛝The slider was located low and below the zone, eliciting a 22.7% swinging-strike rate on Saturday, up from 13.7% in 2026 and 16.4% in his career. Castillo’s slider was thrown 1.3 mph slower, leading to 2 additional inches of downward movement on Saturday.
⏹️Castillo threw his slider in the zone 50% of the time with a 36% chase rate on Saturday. That’s a higher zone rate for the slider than in 2026 (44%) and 2025 (38.8%). However, opposing hitters haven’t been chasing the slider, evidenced by a 26.5% chase rate (2026) and 30.8% (2025).
There have been talks about Castillo and Bryce Miller combining for a start coming soon. After being a pitcher who relied on his stuff, Castillo has interestingly been more of a command pitcher, given his 111 Location+ and 98 Stuff+ in 2026 before Friday.
Trey Yesavage, SP, Blue Jays
Toronto Blue Jays’ Trey Yesavage has been adjusting his pitch mix in 2026. Yesavage had a 17.2% swinging-strike rate and a 34% ball rate on Saturday against the Angels.
📉Yesavage lowered his four-seam (40%) usage against right-handed hitters, adding more splitters (31%) and sliders (29%). That’s notable because Yesavage may need to rely upon his non-fastballs to find success for whiffs.
🪓Yesavage’s splitter elicited a 25% swinging-strike rate while being thrown in the zone 34% of the time. Meanwhile, Yesavage’s 43% splitter chase rate on Saturday was significantly higher than his chase rate in 2026 (27.3%) and 2025 (44.4%).
🛝Like Yesavage’s splitter, he threw his slider low and below, given his 36% zone rate and 57% chase rate on Saturday. That aligns with Yesavage’s slider swinging-strike rate at 27.3%. Yesavage had a similar slider zone rate, yet opposing hitters hardly chased (22.2% of the time).
Yesavage has been making adjustments in early 2026. That leads to slightly more intrigue, yet he can be inconsistent as a pitcher who relies on stuff (105 Stuff+) than command (96 Location+).
Spencer Strider, SP, Braves
The velocity was up for the Atlanta Braves’ starting pitcher Spencer Strider’s four-seamer (+1.8 mph) and slider (+1.3 mph) on Saturday against the Dodgers. That’s the highest four-seam and slider velocity since 2024.
🆙That led to Strider’s four-seam adding 2 inches of induced vertical break and the slider losing 3 inches of downward movement. Strider’s four-seam was located in the upper parts of the zone to generate whiffs with his above-average 17 inches of IVB.
🛝Strider’s slider was eliciting whiffs low and below the zone, including a few low/inside toward left-handed hitters. His slider elicited a 21.9% swinging-strike rate on Saturday, closer but not quite toward his career average (26% SwK).
If Strider maintains the added velocity to help his four-seam and slider pitch movement profiles shift into the above-average range, we should see better stuff metrics.