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How MLB Umpires Impact Baseball Betting Strategy & Where To Track Them

It looks like we’re moving towards a future with self-driving cars, metaverses and artificial intelligence. Eventually, we’ll probably have automated umpires instead of the human ones we have today but in the meantime, bettors must adjust for the mortal version. Anyone who has bet on America’s knows that umpires impact baseball betting.

The main element of evaluating a baseball bet is the game between the two teams and the specific intricacies of how they match up. One element that often gets overlooked is accounting for the man who calls balls and strikes. If you’ve been wondering how to factor in the umpire, here’s how to consider this component in your handicapping.

  • Certain Umpires Have Tendencies
  • Umpires & Pitcher Styles Can Clash
  • Some MLB Umpires Have A Home-Team Bias
How MLB Umpires Impact Baseball Betting
How MLB Umpires Impact Baseball Betting


Certain Umpires Have Tendencies

When we’re talking about accounting for how MLB umpires call the games, what we’re really talking about is the human element. Some umpires are going to be looser with their strike zones and call a pitch a strike that might stretch out of the strike zone. At the same time, other umps might have smaller strike zones and be more favorable to calling balls. If this happens consistently for every pitch, for every at-bat, for every inning, that’s when we can start to see how an umpire can change the course of a game. More balls leads to more walks or more counts that are favorable to hitters. Meanwhile, more strikes leads to more outs and more counts favorable to pitchers. One can deduce how these tendencies can impact a game to being either high-scoring or lower-scoring.

Let’s look at some numbers courtesy of Swish Analytics. As of the start of 2023, Randy Marsh has been behind home plate for 46 games while Erich Bacchus has 53 games on his resume. Take a look at the differences in batting average and runs per game:

Erich Bacchus

Batting Average: .224

Runs Per Game: 7.92

Randy Marsh

Batting Average: .279

Runs Per Game: 10.57

You can clearly see that checking in on who the umpire is behind the plate is something that is not only part of the equation for baseball betting, it has to be one of the first things you examine. Marsh is quite friendly to hitters and we can see that as his games tend to be high-scoring. Bacchus is the opposite, calling the zone more favorably to pitchers. That’s why batters hit for a far worse average in his games and the contests tend to be lower scoring.

If you’re ever betting the totals in Major League Baseball, you have to know who the umpire behind home plate is because this has huge implications on a game going over or under.

Umpire & Pitcher Styles

Now that we know the umpires have certain tendencies, we can start to pair them with the pitchers on the mound and figure out who’ll benefit and who’ll struggle. Greg Maddux is a Hall of Fame pitcher who was known for his impeccable pitch location. He made a living of painting the corners. Well, you can imagine how he’d fare if the umpire behind home plate was calling a tighter strike zone than usual. He might start to get squeezed, not getting strikes he normally does. He might walk more batters and then have to go further into the strike zone, which presents more danger to him.

Meanwhile, let’s say the same situation happened to another legend like Randy Johnson. Johnson was a monster on the mound who used his velocity to overpower batters. He had a tall frame and a long wingspan, so there was actually a shorter point between him releasing the ball and home plate, giving the batter less time to perceive what was coming. A pitcher like that isn’t going to be as negatively impacted by an umpire who calls a tighter strike zone.

Once you can understand the style of the umpire calling the game and correlate that with the style of starting pitcher on the bump, you can get a better idea of which team might struggle and which team might thrive given the scenarios.

Home-Field Advantage & MLB Umpires

Although umps are supposed to be neutral, unfortunately home crowds can have an impact on some of them. Everyone wants to believe that there’s no home team bias and the league can publicly state whatever sounds good to them, but the data says otherwise. 

In 2022, Dan Merzel was the best ump for home teams. The teams playing in front of their own fans went 23-9 in Merzel’s games and bettors wagering $100 per game were up $960. If you want to wash that away as an aberration, then 2021 becomes hard to explain. In that year, home teams were 16-6 in Merzel’s game. Is that a coincidence? These are situations where you want to consider runline betting too.

Let’s examine another ump: Adam Hamari. In 2022, home teams were 19-12, in 2021 they were 15-2 and in 2020, they were 9-5. This looks like a pretty good trend. 

Maybe it’s that some umps just tend to get wooed by the home crowd and don’t want to disappoint the fans. Whatever the case, there’s a pattern here and you can make money off of it.

Use Info on Umpires For MLB Player Props

One forgotten element of umpire handicapping in baseball tends to be how it impacts player props. Most bettors will go directly towards the total when they see who’s umping the game or think about which side makes more sense. However, you can find some great value with player props based on who is calling the game. Better yet, sportsbooks tend to take the ump factor into account for the side and total; fewer books adjust the player props.

In case it’s not fully clear, the logic is quite simple: if you seem umps favorable to pitchers, then you might bet under on the hitter props. If you see umps that have a history of having higher-scoring games or batting averages, then overs on some of the props will make sense.

Don’t use this as the sole piece of evidence that you bet a player prop. However, if you liked Bryce Harper over hits based on how he’s playing recently and the pitching matchup, and you have a favorable ump, that can reinforce your decision. 

Cross-Reference The Advanced Metrics With Betting Stats

There are going to be times where assumptions are made based on the advanced metrics but you want to take the betting picture into account before placing your wager. For example, you might see an ump whose games show a lofty batting average and lots of runs. If the oddsmakers are adjusting for that, though, it doesn’t do you a lot of good. 

A great example of this is Todd Tichenor, who has long been known for having some of the highest scoring games when he’s behind the plate. In 2022, his games averaged 11.0 runs. The challenge here is that the oddsmakers are well aware of Tichenor and his tendencies. As a result, they’ll often shade his games higher than the average because they know what’s coming. That means you have to check to see are his games consistently going over the number. If not, there’s no edge here. 

Look for situations where the oddsmakers are not there before you. Don’t just assume that if the metrics and stats look good, that it’ll do enough for you in terms of beating the totals.

Frequently Asked Questions

Where can umpire information be found?

Major League Baseball’s official website will reveal who is the umpire behind the plate for each contest. Other major news sites and Twitter are also good sources.

What sites can reveal the umpire tendencies?

Websites like and will present all sorts of data on how MLB umpires call games.

What is the over-under?

The over-under is a number set by the oddsmakers for a projected final score of a baseball game. Bettors have to decide whether the two teams will combine to score more (over) the total or less (under).

Outlier Team
April 6, 2023
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