Sasaki, Roki
Run-prevention profile built on workable command
Preseason / current pace / Bayesian update
Rolling bands shrink current-season signal toward the preseason prior until the sample earns more weight.
| ERA preseason | 4.16 |
| ERA current pace | 4.93 |
| ERA rolling p50 | 4.56 |
| Observed weight | 51% |
Actual percentile with projection tick
100th = best in MLB.
Stuff+ and arsenal context
Stuff+ appears when the current pitch-event scoring artifact includes this pitcher; Arsenal Decomposition remains descriptive support under Stuff+.
Arsenal optimization map
Pitch-shape context from this pitcher’s current arsenal snapshot. Hover a pitch to inspect usage, movement, and bat-missing context.
xwOBA allowed snapshot line
Live snapshot series; true 50/100 PA windows require PA-level logs
Aggregate zone heatmap
Aggregate zone metrics from seasonal Statcast leaderboards.
Usage mix, movement map, and Stuff+ composition
2026 pitch-level arsenal aggregates; current season takes over after 100 tracked pitches across at least 2 pitch types. Descriptive pitch-type Stuff+ composition. Not a promoted predictive metric.
| Pitch | Usage | Pitches | Stuff+ | Status |
|---|---|---|---|---|
| FB | 68.0% | 355 | 102 | qualified |
| SL | 32.0% | 167 | 103 | limited sample |
Renamed from the attempted Kirby Index after audit; true Kirby requires release-angle trajectory data.
Current-season signal
| ERA Δ | +0.24 |
| K% Δ | +0.024 |
| Sample | 56.0 IP |
positive regression
Point projection and range
| Metric | Point | Range | Half-width |
|---|---|---|---|
| Innings | 65.9 | -- | -- |
| Batters Faced | 289 | -- | -- |
| K% | 20.0% | 14.3% to 27.9% | +/- 6.8% |
| BB% | 11.4% | 8.6% to 15.5% | +/- 3.4% |
| Whiff% | 22.7% | 19.4% to 29.1% | +/- 4.9% |
| HR/9 | 1.46 | 0.54 to 2.15 | +/- 0.81 |
| xwOBA Against | 0.345 | 0.272 to 0.379 | +/- 0.054 |
| Barrel% Allowed | 8.9% | 5.6% to 14.3% | +/- 4.4% |
| ERA | 4.69 | 2.52 to 6.54 | +/- 2.01 |
| FIP | 4.78 | 3.45 to 5.82 | +/- 1.18 |
| WHIP | 1.344 | 0.967 to 1.699 | +/- 0.366 |
103 career BF
| xwOBA | 0.308 |
| K% | 15.3% |
| BB% | 14.4% |
| Barrel | 12.0% |
101 career BF
| xwOBA | 0.285 |
| K% | 16.6% |
| BB% | 9.9% |
| Barrel | 9.8% |