The Math of Sports Betting: Series Prices

After Miami Heat’s game three blowout of the Boston Celtics to go up 3-0 in the Eastern Conference series, a myriad of tweets and clips of gamblers betting the Heat series started going viral.

Barstool posted a tweet that @PFTCommenter bet $10,000 to win $1,000 on the Miami Heat because nobody had ever come back from being down 0-3 in the NBA playoffs.

I stumbled across a guy named Chad here in Las Vegas betting multiple directions on the Heat throughout the series. One of the videos he posted caught my attention.

I’ll Come Clean

After game 3, I almost made a similar bet. I had a couple hundred bucks sitting in one of my accounts and saw a better line available (I believe it was -1000).

I figured, why not grow that lump sum by 10% over the course of a week max.

So I don’t fault Chad for making this bet on its merit that the Heat were the better team, up 3-0 in the series, and still had two home games left to eliminate the Celtics.

Before I hit submit, I did some math.

The Odds

According to Sports Odds History, the odds before the series started was Miami +400 and Celtics -550 to win the Eastern Conference.

The closing moneyline at Caesars Sportsbook for each game:

  • Game 1: MIA +290 | Boston -375
  • Game 2: MIA +335 | BOS -435
  • Game 3: BOS -185 | MIA +150
  • Game 4: BOS +105 | MIA -130
  • Game 5: MIA +240 | BOS -303
  • Game 6: BOS -141 | MIA +118
  • Game 7: MIA +235 | BOS -294

Aside from Game 4, Miami was the underdog for ever game at tipoff.

The Math

After Game 3 the series price moved Miami between -800 and -1200 depending on the book.

It was enticing. Miami were clearly the better team in the first three meetings. And the number made lot of noise on Gambling Twitter.

But taking the series price was the lazy, more expensive way to bet.

In the TikTok video posted to Twitter, Chad was betting to win $45. He got -1100 odds, which meant he had to bet $500.

But instead, he could have bet each game to win $50, including the amount it would take to recoup any money lost until the series was over.

Game 4

Chad would have had to only bet $65 to win $50. This would be presumed to be a relatively safe bet. It’s not astronomically high moneyline price for a home team that’s dominated throughout the series.

Ultimately, that bet would have lost, so the next bet he’d need to make $115 to win $50 on the series.

Game 5

Now Chad would need to bet to win $65 for the Game 4 bet in addition to his $50 goal. The odds follow a similar trend of Games 1 and 2, which mean Miami is a massive underdog yet again.

At +240, Chad would have only needed to bet $48 to win $115.

The Heat would lose this game and now Chad would need to bet to win $163 in the next game.

Game 6

Boston looked good in Game 5, the markets reacted, so oddsmakers made Miami a small home underdog at +118. To this point, Chad would be down $113.

A small underdog is a big bonus. Chad would need to bet $138.14 to win $163 in Game 6, recouping all the money he’s lost and winning $50 for the series.

The Celtics had the miraculous win at the buzzer, which led to a Game 7 in Boston.

Game 7

At this point, the total staked (and lost) would be $251.14. But, Miami would yet again be heavy underdogs at +235. So to win back the money lost and win $50 for the series, Chad would have only needed to bet $128.15 to win $301.14.

Obviously, the Heat prevailed, blowing out the Celtics on the road.


The total bet would have been $379.29, not $500.

That’s $120.71 cheaper. The theoretical odds would have been -758 for the series price.

The benefit isn’t just the lower risk, but the choice to skip a game or play the odds differently.

I don’t think Chad made a bad bet, I almost made the same one. But when you’re betting short-term futures, there’s often little value in betting the price over betting each game individually.

Series Prices Have Value

Series prices often only have value before the series starts. Often that value is only found on favorites. It’s safe to presume that series underdogs will be underdogs in the majority of the games played.

When considering to bet a series price, look at the individual game odds, take a little time, do some math, and you’ll frequently see that the casinos are charging a premium.