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Umpire Grade · Blue Notes

Junior Valentine

21 games graded behind the plate.

B+
Season Grade
93.7% ± 0.8
0.47
Avg Swing
runs / game
53.7%
ABS Overturns
43/80 calls

3,085 correct of 3,291 graded takes (93.7% ± 0.8, 95%). Best game 97.0% · worst 90.7%. Grade is accuracy on taken pitches vs the rulebook zone; ABS is the Automated Ball-Strike System challenge record (how often the robots overruled the call).

What we can't say about Junior Valentine

This season is 3,291 graded takes, which puts Junior Valentine's overall accuracy at 93.7% ± 0.8 (95% interval). That is a real measurement against a league spanning about four points end to end. It is not enough for anything finer, and here is the arithmetic rather than our word for it:

  • how the zone moves with two strikes about 658 takes, so ±1.9 points. (the league-wide two-strike effect is about 1 point in 2026.)
  • any single corner of the zone about 274 takes, so ±2.9 points. (corner cells are where umpires actually differ.)
  • whether one pitcher is called tighter than another about 55 takes, so ±6.4 points. (a given pitcher is worked once or twice a season.)

And a note on the number itself: an accuracy figure is a rate plus a convention for what counts as a miss. Ours grades every taken pitch against the rulebook zone as the feed reports it. Others are more forgiving — UmpScorecards counts a call wrong only when the pitch was at least 90% likely to be a strike — so two sites can print the same percentage about the same umpire and not mean the same thing by it. How the grade is built.

The overturn rate is a different kind of number and does not belong beside the grade: it is accuracy on the 80 pitches players chose to challenge, which are the pitches they already believed were wrong. 80 is enough to print it with its own denominator, which is what we do — but it still ranks umpires by how often they are appealed, not by how often they are right.

The road to the plate

Junior Valentine

From a teaching license in Tennessee to the full-time MLB staff — the road to the plate.

Junior Valentine was born on October 21, 1987, in the town of Cosby, Tennessee. He graduated from Maryville College with a degree in history and a teaching license, then attended the Wendelstedt Umpire School in 2011. Nine full years passed between that enrollment and his first major league game. He debuted on August 26, 2020, called up to work a Yankees-Braves doubleheader in Atlanta, and he wore uniform number 25. Three seasons after that debut, in 2023, he was promoted to the full-time MLB umpiring staff.

The 2023 season held two games behind the plate that drew attention for different reasons. On May 9, he worked a Royals-White Sox matchup and missed just one call throughout the contest, earning praise for calling a near-perfect game. On June 24, a controversial balk he called on Astros pitcher Ryne Stanek allowed the Dodgers to score the go-ahead run in an 8-7 victory, drawing significant attention. Two years before the promotion to the full-time staff, on September 13, 2021, Valentine was on the field when a throw from Edmundo Sosa hit him in the face during a game. He remained in the game after the throw and continued officiating.

His special assignments since the promotion include Wild Card Games and Series in 2024 and 2025, as well as the MLB Speedway Classic in 2025. He serves on Jordan Baker's umpiring crew and is not a crew chief. Fever has graded him behind the plate in 19 games during the 2026 season to date.

Reporting: Wikipedia, Close Call Sports. Umpire data: MLB StatsAPI, via the Fever engine.

By the Desk · filed 2026-07-24 — the profile reads as of its filing; the grading record above is live · every fact in this piece comes from a sourced research pack and clears an independent fact-check, and nothing is edited after filing.

The games

GameGradeFavorABSBlue Note
SEA @ NYY2026-08-12A0.2 SEA2/4A workmanlike night — nothing to frame, nothing to fix.
STL @ TOR2026-07-31A0.2 STL0/1Called it the way the rulebook drew it up.
LAD @ NYY2026-07-17C+0.9 NYY2/4The zone kept to itself — the hitters said thanks.
COL @ SF2026-07-09B0.1 COL0/2The kind of night where the umpire is the least of the story.
MIA @ ATH2026-07-05B0.2 MIA5/7The challenge cart got its steps in.
TB @ KC2026-07-01B+0.7 TB0/0Called a fair game and let the players decide it.
MIA @ STL2026-06-26A-0.1 MIA3/5Called a fair game and let the players decide it.
CHC @ NYM2026-06-23A1.0 CHC4/6Somebody's pitching staff sent a thank-you note.
SF @ ATL2026-06-17A0.2 ATL2/2The zone showed up, did the job, and went home. Ideal.
MIA @ PIT2026-06-12A-0.1 MIA1/3The kind of night where the umpire is the least of the story.
MIL @ COL2026-06-07B1.1 MIL5/9Hawkeye clocked in early and stayed late.
LAD @ AZ2026-06-03B+0.5 AZ0/2Solid and unspectacular — exactly what the job asks.
CLE @ PHI2026-05-22B+0.8 CLE0/3The zone kept its promises.
MIL @ MIN2026-05-17A-0.1 MIL4/6Reliable as a Tuesday: no complaints, no headlines.
DET @ NYM2026-05-13B-0.1 DET3/6A workmanlike night — nothing to frame, nothing to fix.
MIL @ WSH2026-05-01A-0.1 MIL2/5Reliable as a Tuesday: no complaints, no headlines.
SD @ AZ2026-04-26A0.6 SD0/0A workmanlike night — nothing to frame, nothing to fix.
LAD @ SF2026-04-21C+1.3 SF3/6One dugout got the friendlier version of the evening.
SF @ CIN2026-04-16B+0.5 SF3/4Solid and unspectacular — exactly what the job asks.
TOR @ CWS2026-04-04B+0.6 CWS2/3Reliable as a Tuesday: no complaints, no headlines.
PIT @ CIN2026-03-30C+0.6 CIN2/2The zone shrank when the pitchers needed it most.