You Should Always Bet on MLB Run Lines in These 6 Situations

Smiling Man Holding Cash And the MLB Logo on a Baseball on Left

Sports betting trends are powerful tools that bettors can use to supplement or enhance their handicapping and betting strategy.

Major League Baseball is just as vulnerable to betting trends as any other sports, though some bettors think the baseball market is more difficult to break into due to tighter scores, massive ever-changing rosters, and a much longer regular season than other pro sports.

This post will help you identify situations where betting on baseball’s run line makes good financial sense. I’ll start with a basic outline of what run lines are, why they’re used, and why they matter. Then I’ll outline those six situations where bets on the MLB run line make sense.

The MLB Run Line vs. the Point Spread

The average margin of victory in the NFL is around 5 points. In the NBA, it’s 9 points. In baseball, it’s right at about 1 run. That makes creating a traditional point spread for baseball betting inefficient and may be impossible.

So, there’s no point spread in baseball. Instead, books depend on the run line, a 1.5 run differential that handicaps the favorite and gives the underdog a boost. The run line’s function is identical to the point spread, but because baseball scores tend to be tighter than in other sports, the risk and payouts vary rather than the number itself.

Here’s a made-up example of what a baseball run line might look like at a real money sportsbook in the USA:

Houston Astros -1.5 (-160)

Texas Rangers +1.5 (+180)

The run line is represented right next to the team’s names. The Astros are the favorite since their run line is listed as a negative number. The Rangers are the underdog – their run line is a plus number.

In parentheses next to the run line are the odds you’ll get for backing either side. Backing the Astros gives you a minus number, meaning you’d have to bet $160 to win back $100. The Rangers are represented by a plus number, indicating that a winning bet of $100 would pay out $180.

How does the run line benefit the underdog? If the Rangers lose by a single run, a bet on their side is still a winner. The Astros are handicapped because, for a bet on the ‘Stros to pay off, they have to win by at least two runs.

When to Avoid Run Line Bets

While I’m an emphatic believer in baseball run line betting, I’m also convinced that there are several situations where you should avoid it.

When you don’t understand it.

Don’t place a bet if you don’t know what you’re betting on. In short, don’t place a run line bet just for the sake of placing it. This one’s easy to fix – learn about the run line, read the rest of this post, and become more confident.

MLB Player Pete Alonso

When you want to bet on the home team.

Home teams don’t do a great job of covering the run line. I could write three or four posts on the reasons for this, but for the purpose of this post, just understand that backing a home team to cover the run line is a tough position, and that’s based on decades of game trends.

When you want to bet on a road favorite.

Betting on road teams is good – I’ll cover this more in the next section – but backing road favorites to cover the run line is even more dangerous than blindly backing home teams. A team rarely covers the run line more than 45% of the time in a given season in games where they’re favored on the road. There are contexts in which road teams are good to back, but not when they’re the favored team.

When to Bet on the Run Line

The six situations below outline when a run line bet makes the most sense, odds-wise.

Situation #1 – Betting on an Away Team

Don’t sleep on road teams covering the run line.

Paradoxically, even though road favorites fare poorly against the run line, it makes good financial sense to focus on road teams in general when considering a run line cover bet. When these teams are favored, their win percentages drop.

It’s when they’re traveling as underdogs that their cover percentage tends to increase into the profitable zone. Almost every club in Major League Baseball has covered enough on the road to represent potential profit.

Situation #2 – When One Team is Heavily Favored

I’m always suspicious of heavy favorites in baseball. It’s a parity-driven league, full of streaks both good and bad, and no team is ever really as likely to win as the books make it out. Any time I see a bloated line, in either direction, I’m looking for a good money line opportunity.

Situation #3 – Betting on a Home Dog

You should consider the run line when you’re looking to back an underdog playing at home. In the 2021 season, 12 clubs won often enough as home dogs that you could’ve backed them blindly and turned a profit.

This is a multi-year trend. Since 2011, every team in baseball has covered the run line in at least 52% of games where they were listed as home underdogs. 7 teams (Tampa Bay, the Dodgers, the A’s, the Pirates, the Nationals, the Cardinals, and the Brewers) have covered in at least 60% of these situations.

MLB Dodger at Bat

Obviously, some teams face more home dog situations than others. The teams that have been identified most often as home dogs (the Tigers and Diamondbacks) are sitting at a more typical 52% win rate as home dogs.

Situation #4 – During the Second Game of a Back-to-Back Series

Here’s a bit of contentious advice – when a team is playing in the second of two back-to-back games, you should always bet against the run line. No team, going back to 2011, has won a significant percentage of their games on no rest. In fact, most MLB clubs win less than 50% of games on no rest, and even when they do pull off a win, it’s most often of the one-run variety.

Situation #5 – When a Team is Well-Rested

Backing a team on the run line when they have 3 or 4 days rest leads to a potentially profitable betting strategy. If you back the right teams, you can beat the book by pouncing on high-rest games featuring teams with lots of powerful bats. To wit, the best teams against the run line on heavy rest are the hardest-hitting teams in the league: Houston, Toronto, LA, Minnesota, etc.

It should be obvious why lots of rest is good for teams. Books know this, so you won’t often get great odds in this situation. But you’re at such an advantage, it’s hard to pass it up.

Situation #6 – During the Regular Season Only

Honestly, you probably shouldn’t be betting on the run line during the playoffs. The regular season is fair game, and if you can identify the situations in this post in the real world, you’ll do well with run-line bets. But I can’t guarantee any of the trends are at play when the postseason rolls around.

Going back through ten years of playoff results, it’s clear that even teams who do well against the run line seem to fall apart against the book’s line in October. Just ten clubs have won enough to break even, while most of the league is only beating the run line about 40% of the time in the postseason.

Obviously, if your baseball handicapping has given you some insight that makes you think you can beat the run line in October, go for it. If you enjoy betting on the run line and you don’t want to stop for the postseason, that’s fine. The outcomes are a lot more varied, and you’ll probably have a harder time winning.

In Summary

Don’t be afraid of the run line. It’s a simpler point spread. The game of baseball just doesn’t lend itself to point spread betting, so making bets on the run line is the next best alternative. In the right context, run-line betting is just as good as any other type of baseball bet.

Run line bets can be just as successful as money line or game totals, you just have to know in what situations you’ll be at an advantage. Follow the advice in this post, give some run-line betting a try, and report back what you learn.