As the 2025 Major League Baseball season gets underway, fans will be focused on star players, pitching matchups, and playoff races. But behind every inning, every play at the plate, and every close call, there’s another key part of the game — the umpiring crew.

From calling balls and strikes to enforcing new rules, MLB umpires play a critical role in maintaining the flow and fairness of the game. Here’s a breakdown of their roles, responsibilities, and what to watch for this season.

‍

Umpire or Referee: What's the Correct Term?

In baseball, the correct term is umpire, not referee. While “referee” is common in sports like basketball or football, “umpire” refers specifically to officials in baseball and softball.

‍

Umpire Crew Roles in a Typical Game

MLB games are officiated by a four-person crew:

1. Home Plate Umpire
   • Calls balls and strikes
   • Handles fair/foul decisions around the plate
   • Oversees timing, substitutions, and rule enforcement
   • Communicates challenges and replay requests
2. First Base Umpire
   • Rules on plays at first base
   • Watches check-swings from left-handed batters
   • Assists with fair/foul calls along the first-base line
3. Second Base Umpire
   • Covers tag plays, force outs, and pickoffs at second base
   • Shifts position based on runner situations
   • Assists on fly ball rulings and infield decisions
4. Third Base Umpire
   • Handles plays at third
   • Watches check-swings from right-handed batters
   • Helps with line calls and deep fly ball judgments

During postseason games, the crew expands to six umpires, with two additional officials positioned in the outfield.

‍

Key Responsibilities of MLB Umpires

• Calling balls and strikes with accuracy and consistency
• Monitoring pace-of-play and enforcing new pitch clock rules
• Handling replay reviews and initiating umpire crew conferences
• Enforcing mound visit limits, batter box rules, and other in-game protocols
• Managing player and manager conduct, including issuing warnings or ejections
• Communicating with league officials during controversial or reviewable moments

‍

Replay Review in 2025

MLB’s replay review system continues to evolve. As of 2025:

• Each team is allowed one manager challenge per game
• If a challenge is successful, they retain it
• Reviews are conducted at the MLB Replay Center in New York
• Umpires signal the call and outcome via headset after video review

Certain plays — like home run boundary calls and fan interference — may also be reviewed automatically.

‍

Notable Umpires to Watch in 2025

Some umpires gain recognition for their consistency, accuracy, or presence in high-stakes games. A few notable names for the 2025 season:

• Laz Díaz – Veteran umpire known for postseason experience
• Tripp Gibson – Among the highest-rated in strike zone accuracy metrics
• Pat Hoberg – Gained attention for calling a perfect game (100% accuracy) in the 2022 World Series
• Angel Hernández – Long-time figure who continues to draw both praise and criticism from fans
• Quinn Wolcott – A younger ump with strong command presence and increasing assignments in key games

Expect postseason crews to feature a mix of long-tenured officials and rising talent.

‍

New Rules and Challenges for Umpires in 2025

As MLB continues to adapt the game for speed and entertainment, umpires are tasked with enforcing new regulations. This season, key areas of focus include:

• Pitch clock enforcement and associated ball/strike penalties
• Batter box violation enforcement
• New disengagement limits for pitchers (step-offs or pickoff attempts)
• Replay speed improvements to minimize downtime
• Strike zone analysis through ongoing automated zone comparisons

While automated strike zones (robot umps) are being used at some levels of the minor leagues, MLB continues to rely on human umpires behind the plate for now.

‍

Umpire Scheduling and Travel

MLB umpire crews rotate throughout the league and are scheduled in crews that change throughout the season. Each umpire typically works home plate once every four games and rotates through the bases in the remaining games.

Umpires work an average of 120–140 games per season, often traveling thousands of miles between series.

‍

Final Thoughts

MLB umpires are essential to the rhythm, rules, and fairness of every game played during the 162-game grind. While fans may not always notice their presence unless a call is controversial, their preparation and performance directly impact the flow and integrity of the sport.

As the 2025 season rolls forward, expect umpires to continue adapting to evolving rules, increased transparency, and the growing scrutiny that comes with expanded replay and digital analysis.