Riley O'Brien
STL • P • Throws R • 2026 Season
Yahoo eligible: RP
Value
Standard score (σ), not a percentile, vs all qualified pitchers — 0 = average, +1 = one standard deviation above the mean. Built from 5x5 category z-scores (like Baseball Monster).
Consensus Rank
Composite of 1 in-season expert ranking sources (FantasyPros ROS consensus + Pitcher List) — blended so it matches no single site, ranked among pitchers (lower = better).
Control & Efficiency
Strike-throwing and length profile — drives the Likely-QS / High-K/BB start flags. The bar under each stat is this pitcher's percentile vs 207 qualified MLB starters (100th = best — already direction-adjusted, so a low BB% or P/PA scores high).
Arsenal
Throwing hand and pitch mix (share of pitches thrown) — the traits the matchup ratings below weigh against each opponent's splits.
Primary pitch: Sinker (100%)
Season Stats
The big number is the actual stat. The bar below it is this pitcher's percentile vs 385 qualified MLB pitchers (≥30 IP) this season — 100th = best, direction-adjusted (a low ERA/WHIP/BB scores high).
Splits & Tendencies
How this pitcher fares by batter hand, venue, opponent lineup quality (elite→poor offenses), and over the last 30 days. Lower ERA/WHIP is better; OPS-against shows for the hand/venue splits. Hover a tag for the numbers.
| Split | IP | ERA | WHIP | K/9 | BB/9 | OPS-agst |
|---|---|---|---|---|---|---|
| vs LHB | 22.1 | — | 1.39 | 7.7 | 4.8 | .679 |
Luck Factor
How much this pitcher's results are outrunning or trailing the quality of what actually happened — league-relative. Hover a meter for the inputs.
Game Log (46 games)
| Date | Opp | Dec | IP | H | R | ER | BB | SO | HR | P |
|---|---|---|---|---|---|---|---|---|---|---|
| Aug 5 | @ New York Yankees | - | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 22 |
| Aug 2 | @ Toronto Blue Jays | - | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 18 |
| Jul 30 | vs Chicago Cubs | - | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 17 |
| Jul 29 | vs Chicago Cubs | - | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 18 |
| Jul 22 | @ Los Angeles Angels | - | 1 | 0 | 0 | 0 | 2 | 3 | 0 | 26 |
| Jul 20 | @ Los Angeles Angels | L | 0.1 | 2 | 2 | 2 | 1 | 1 | 0 | 21 |
| Jul 17 | @ Arizona Diamondbacks | - | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 16 |
| Jul 11 | vs Atlanta Braves | - | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 18 |
| Jul 10 | vs Atlanta Braves | - | 1 | 0 | 0 | 0 | 0 | 2 | 0 | 12 |
| Jul 8 | vs Milwaukee Brewers | - | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 15 |
| Jul 4 | @ Chicago Cubs | - | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 13 |
| Jun 30 | @ Atlanta Braves | - | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 9 |
| Jun 28 | vs Miami Marlins | - | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 15 |
| Jun 22 | vs Arizona Diamondbacks | - | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 17 |
| Jun 21 | @ Kansas City Royals | - | 1 | 2 | 2 | 2 | 0 | 1 | 1 | 12 |
| Jun 16 | vs San Diego Padres | - | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 13 |
| Jun 13 | @ Minnesota Twins | - | 1 | 0 | 1 | 1 | 3 | 1 | 0 | 31 |
| Jun 7 | vs Cincinnati Reds | - | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 15 |
| Jun 6 | vs Cincinnati Reds | - | 1 | 2 | 0 | 0 | 1 | 1 | 0 | 23 |
| Jun 3 | vs Texas Rangers | - | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 13 |
| Jun 2 | vs Texas Rangers | L | 1 | 3 | 3 | 3 | 1 | 2 | 0 | 32 |
| May 29 | vs Chicago Cubs | - | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 14 |
| May 23 | @ Cincinnati Reds | L | 1.1 | 0 | 1 | 0 | 1 | 2 | 0 | 20 |
| May 19 | vs Pittsburgh Pirates | - | 1 | 2 | 2 | 2 | 1 | 0 | 0 | 22 |
| May 15 | vs Kansas City Royals | - | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 10 |
| May 14 | @ Athletics | - | 1 | 0 | 0 | 0 | 0 | 2 | 0 | 16 |
| May 12 | @ Athletics | - | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 13 |
| May 10 | @ San Diego Padres | - | 1 | 2 | 2 | 2 | 0 | 3 | 1 | 31 |
| May 7 | @ San Diego Padres | - | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 10 |
| May 4 | vs Milwaukee Brewers | - | 0.2 | 0 | 0 | 0 | 0 | 0 | 0 | 3 |
| May 2 | vs Los Angeles Dodgers | - | 1 | 4 | 2 | 2 | 0 | 2 | 0 | 26 |
| Apr 29 | @ Pittsburgh Pirates | - | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 11 |
| Apr 25 | vs Seattle Mariners | L | 1 | 4 | 2 | 2 | 1 | 1 | 0 | 39 |
| Apr 21 | @ Miami Marlins | - | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 17 |
| Apr 19 | @ Houston Astros | W | 1.1 | 1 | 0 | 0 | 0 | 2 | 0 | 19 |
| Apr 18 | @ Houston Astros | - | 0.2 | 0 | 0 | 0 | 0 | 1 | 0 | 7 |
| Apr 15 | vs Cleveland Guardians | - | 1 | 0 | 0 | 0 | 0 | 2 | 0 | 15 |
| Apr 14 | vs Cleveland Guardians | W | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 15 |
| Apr 10 | vs Boston Red Sox | - | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 8 |
| Apr 8 | @ Washington Nationals | - | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 15 |
| Apr 7 | @ Washington Nationals | - | 1 | 0 | 1 | 0 | 0 | 2 | 0 | 16 |
| Apr 5 | @ Detroit Tigers | - | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 13 |
| Apr 1 | vs New York Mets | - | 1 | 1 | 0 | 0 | 0 | 2 | 0 | 16 |
| Mar 31 | vs New York Mets | - | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 11 |
| Mar 28 | vs Tampa Bay Rays | - | 1 | 2 | 0 | 0 | 0 | 0 | 0 | 9 |
| Mar 26 | vs Tampa Bay Rays | W | 1.1 | 1 | 0 | 0 | 0 | 2 | 0 | 17 |