Umpire Grade · Blue Notes

Jansen Visconti

24 games graded behind the plate.

Season Grade

93.8% ± 0.8

Avg Swing

runs / game

ABS Overturns

35/86 calls

3,356 correct of 3,579 graded takes (93.8% ± 0.8, 95%). Best game 97.5% · worst 89.6%. 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 Jansen Visconti

This season is 3,579 graded takes, which puts Jansen Visconti's overall accuracy at 93.8% ± 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 716 takes, so ±1.8 points. (the league-wide two-strike effect is about 1 point in 2026.)
any single corner of the zone — about 298 takes, so ±2.7 points. (corner cells are where umpires actually differ.)
whether one pitcher is called tighter than another — about 60 takes, so ±6.1 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 86 pitches players chose to challenge, which are the pitches they already believed were wrong. 86 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

Jansen Visconti's Two-Year Climb

An umpire who reached the full-time major-league staff in half the time most fill-ins need, with postseason assignments in four consecutive Octobers.

Most fill-in umpires need four or five seasons to earn a permanent major-league position. Jansen Visconti needed two.

He debuted on April 17, 2018. In the 2019 season he officiated 142 games — the highest total among fill-in umpires in the league that year. The workload earned him the UEFL Fill-In Umpire of the Year Award, continuing a pattern in which recipients of that honor went on to receive full-time staff positions. In February 2020, MLB promoted him to the full-time staff. He had worked 250 regular-season games before the promotion arrived. He was described as the greenest hire of that 2020 class, having reached permanent status in half the time the path usually requires.

Visconti is from Latrobe, Pennsylvania. He graduated from the Hunter Wendelstedt Umpire School in 2010 and also attended the Jim Evans Academy of Professional Umpiring while earning a Bachelor of Science in Finance from Penn State University. His professional career began in the Gulf Coast League and moved through the New York-Penn, South Atlantic, Carolina, Eastern, and International Leagues before he reached the majors. He joined the International League staff in 2014 and worked the Futures Game that same summer. He wears uniform number 52.

October

The postseason assignments came each year from 2021 through 2024. Wild Card Series in 2021 and 2024. Division Series in 2022 and 2023. The League Championship Series in 2024. He received an All-Star Game assignment in 2025.

His 18 graded games behind the plate this season are the reason his name appears on this page.

Reporting: Close Call Sports, Baseball Reference Bullpen, Wikipedia, Retrosheet, MLB.com. 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

Game	Grade	Favor	ABS	Blue Note
SD @ TB2026-08-29	A-	0.6 SD	2/4	Nothing that'll trend, and on this beat that's a compliment.
BAL @ STL2026-08-26	A	0.5 STL	0/2	The zone kept its promises.
ATH @ KC2026-08-17	B-	0.0 ATH	1/4	Borderline went to the battery all night.
NYM @ ATL2026-08-11	A-	0.4 ATL	0/2	The kind of night where the umpire is the least of the story.
COL @ STL2026-08-07	A	0.0 COL	1/2	No notes. Well, one: nicely done.
CHC @ PIT2026-07-26	A	0.1 PIT	0/3	The zone showed up, did the job, and went home. Ideal.
NYM @ MIL2026-07-21	B+	0.1 NYM	0/2	The zone kept its promises.
CIN @ COL2026-07-17	B+	0.2 COL	2/3	A workmanlike night — nothing to frame, nothing to fix.
PIT @ PHI2026-07-02	C	0.5 PIT	3/6	The zone stretched its legs.
WSH @ BAL2026-06-28	A	0.3 BAL	1/4	The kind of night where the umpire is the least of the story.
TEX @ MIA2026-06-23	B-	0.3 MIA	2/5	Pitchers earned every strike the hard way.
SEA @ WSH2026-06-13	A-	0.6 WSH	2/5	The zone kept its promises.
PHI @ TOR2026-06-08	A	0.1 PHI	2/3	A workmanlike night — nothing to frame, nothing to fix.
MIN @ PIT2026-05-29	B-	0.1 MIN	1/5	The zone shrank when the pitchers needed it most.
NYM @ MIA2026-05-24	C+	0.5 MIA	4/5	You wanted a strike, you had to earn it twice.
MIL @ CHC2026-05-19	B	0.8 MIL	1/3	A steady night's work behind the plate.
AZ @ TEX2026-05-13	A	0.3 TEX	4/5	Solid and unspectacular — exactly what the job asks.
STL @ SD2026-05-09	B	0.4 SD	2/4	Expanded the plate a touch past its 17 inches.
CWS @ LAA2026-05-05	A	0.1 CWS	2/3	Called it the way the rulebook drew it up.
BOS @ BAL2026-04-24	B-	0.0 BAL	1/2	One of those nights the challenge system was invented for.
MIL @ MIA2026-04-19	A+	0.9 MIL	0/3	The zone kept its promises.
KC @ DET2026-04-15	B+	0.2 KC	1/4	A steady night's work behind the plate.
PHI @ COL2026-04-03	A-	0.9 PHI	2/4	The kind of night where the umpire is the least of the story.
AZ @ LAD2026-03-28	B-	0.1 AZ	1/3	You had to throw it down Broadway to get the call.