Edwin Diaz vs Scott Williamson: Career Stats Comparison
Edwin Diaz has the better career line of the two, leading 9 of the 12 scored categories on this page (4 further counting totals are shown but not scored). Edwin Diaz has played 2016–present as a pitcher; Scott Williamson played 1999–2007 as a pitcher.
- ERA (Earned Run Average):
- Earned runs allowed per nine innings pitched: (ER × 9) ÷ IP. The primary measure of pitching effectiveness.
- W (Wins):
- Games credited to a pitcher whose team took a lead it never surrendered while he was the pitcher of record.
- SO (Strikeouts):
- For a batter, times retired on a third strike; for a pitcher, batters retired on a third strike.
- WHIP (Walks and Hits per Inning Pitched):
- Baserunners allowed per inning: (BB + H) ÷ IP. Under 1.00 is elite.
Data updated
Edwin Diaz (2016–present) and Scott Williamson (1999–2007) — breaking in during the 2010s and the 1990s respectively, so they pitched against very different hitting environments. Edwin Diaz has 30 wins and 867 strikeouts through October 12, 2026; Scott Williamson finished with 28 wins and 510 strikeouts. The numbers below run them through identical career and rate-stat lenses.
Quick answer
- Who had the better ERA? Edwin Diaz, with 3.03 to Scott Williamson's 3.36.
- Who won more games? Edwin Diaz, with 30 to Scott Williamson's 28.
- Who recorded more strikeouts? Edwin Diaz, with 867 to Scott Williamson's 510.
- Who had the better WHIP? Edwin Diaz, with 1.07 to Scott Williamson's 1.30.
- Who pitched more innings? Edwin Diaz, with 538.0 to Scott Williamson's 439.1.
- Who threw more shutouts? Neither — both are at 0.
- Who has the higher career Pitcher PIV? Edwin Diaz, with 21,805 career Pitcher PIV to Scott Williamson's 11,282.
Scott Williamson
Career Stats Side-by-Side
Every cell below is a career total or career rate. Cells highlighted in green mark the player who leads that line. Lower ERA, WHIP and BB/9 lead; higher K/9 leads. 12 of the 16 lines below are scored; the other 4 are counting totals on which fewer is not an achievement, so no one is awarded them. Totals where fewer is not an achievement -- losses, walks and hits allowed -- are left unmarked, because they track how long someone pitched rather than how well. Rate stats are not era-adjusted, and the 2010s and the 1990s were different run environments, so read them against their eras, or use the PIV card below, which is adjusted.
Edwin Diaz is still active — his totals below are current through October 12, 2026.
| Statistic | Edwin Diaz | Scott Williamson |
|---|---|---|
| Wins | Leads: 30 | 28 |
| Losses not scored | 38 | 28 |
| Games | Leads: 541 | 344 |
| Games Started | 0 | Leads: 10 |
| Complete Games | 0 | 0 |
| Shutouts | 0 | 0 |
| Saves | Leads: 260 | 55 |
| Strikeouts | Leads: 867 | 510 |
| Walks not scored | 193 | 244 |
| Hits Allowed not scored | 382 | 326 |
| Home Runs Allowed not scored | 57 | 35 |
| Innings Pitched | Leads: 538.0 | 439.1 |
| ERA | Leads: 3.03 | 3.36 |
| WHIP | Leads: 1.07 | 1.30 |
| K/9 | Leads: 14.50 | 10.45 |
| BB/9 | Leads: 3.23 | 5.00 |
PIV Comparison through 2025
By PIV (Player Impact Value), Edwin Diaz outpaces Scott Williamson 21,805 to 11,282 — driven by per-season impact — 2,423 PIV per season to 1,026 — rather than by longevity, since Edwin Diaz played 9 seasons to Scott Williamson's 11. PIV adjusts each season to league baselines, so it's the cleanest way to compare careers across eras.
PIV is computed through the 2025 season. The career totals on this page include 2026 to date, so PIV does not yet reflect the 2026 season.
Peak Seasons
The best single seasons each player produced, ranked by ERA among qualified workloads (120+ innings).
Edwin Diaz
No seasons meet the qualifying workload, so there is no peak-season list to show.
Scott Williamson
No seasons meet the qualifying workload, so there is no peak-season list to show.
Verdict
On the head-to-head card, Edwin Diaz leads in wins, strikeouts, ERA, and WHIP, while Scott Williamson owns no headline categories. That doesn't settle the era debate, but on the raw scoreboard the edge goes to Edwin Diaz. PIV agrees: Edwin Diaz grades out higher across their careers. Click through to each profile for the full season-by-season breakdown.
Related Matchups
How the Edwin Diaz and Scott Williamson careers compare
No season is shared: Scott Williamson played 1999–2007, Edwin Diaz 2016–present. The table compares 541 games of Edwin Diaz with 344 of Scott Williamson across 9 and 11 PIV seasons; totals favor the longer career by default. The green cells for Scott Williamson are starts (10 to 0). The per-nine rows read 14.50 strikeouts and 3.23 walks for Edwin Diaz, 10.45 and 5.00 for Scott Williamson. Edwin Diaz worked mostly in relief (0 starts in 541 games, 260 saves), and Scott Williamson worked mostly in relief (10 starts in 344 games, 55 saves). In WHIP, Edwin Diaz's 1.07 beats Scott Williamson's 1.30. Edwin Diaz's numbers are live and update with each game, so the comparison is a snapshot.
Edwin Diaz vs Scott Williamson: Frequently Asked Questions
- Who was better, Edwin Diaz or Scott Williamson?
- By the career statistics compared on this page, Edwin Diaz leads Scott Williamson in 9 of the 12 scored categories.
- Who had the better ERA?
- Edwin Diaz, with 3.03 to Scott Williamson's 3.36.
- Who won more games?
- Edwin Diaz, with 30 to Scott Williamson's 28.
- Who recorded more strikeouts?
- Edwin Diaz, with 867 to Scott Williamson's 510.
- Who had the better WHIP?
- Edwin Diaz, with 1.07 to Scott Williamson's 1.30.