Gambling Tips > Blackjack

FACTS OF SPLITTING 8s AGAINST A 10

By Henry Tamburin


The May 2009 issue of Casino Player magazine contains an interview with gambling writer and maverick John Patrick, who advocates an “unorthodox” approach to gambling. In the interview, Patrick offers this explanation (in his words) as to why he wouldn’t split a pair of 8s against a dealer 10 and instead would surrender the hand:

 

“If you’re playing blackjack for $10 a hand and you are dealt two eights and the dealer has a king showing, the book says to split. So you split and you put another $10 up there. Now, there’re gonna give you a card on each eight, which means you have one eight with a card for $10, and another eight with another card for $10. The dealer still has that king showing. How have you improved your situation? Why would you take a bad hand of two eights and turn it into two bad hands, when you admittedly are inferior to the dealer’s hand?” Patrick then goes on to say that if he were dealt this hand, “I’d surrender. I’m gonna lose that with two eights. I give it up. I tell the dealer, “Go ahead, take half my bet.” I’d rather play a hand I’m going to win.”

 

On the surface, Patrick’s analysis of splitting 8s against a 10 seems convincing. In fact, most players agree with Patrick and would never split. Unfortunately, that’s a big mistake, and here’s why.

 

There is no question that the dealer has the upper hand when you hold a pair of 8s against her 10. The math says she’ll make a pat (17-21) hand about 77 percent of the time (assuming she doesn’t have a blackjack), and she has only a 23 percent chance of busting. So, there is no argument here: you are the underdog, period. But, what Patrick and others fail to grasp is the following:

 

Even though you are the underdog when you are dealt a pair of 8s against a dealer 10, you are less of an underdog when you split the 8s and play two hands with an 8 on each hand.

 

So, the real question that you should ask yourself is this: If I’m going to lose money on this hand no matter how I play it (and you will), which strategy cuts my losses?  Is it hitting, standing, splitting, or as Patrick suggests, throwing in the towel and surrendering?

 

The only way to know for sure which strategy is best is to calculate in dollars how much you can expect to lose using each strategy and then compare the results. Agreed? And the math to do this calculation is, surprisingly, quite simple. (For the following analysis, I assumed a standard game: 6-deck, s17, das, and resplitting allowed up to four hands.)

 

What we positively, absolutely, know about hitting or standing on 16 against a dealer 10 is this: on average you will win this hand only 23 times out of 100 (hey, I told you this was a bad hand). (Note: The actual win percent to two decimal places is 23.22 for hitting and 23.16 for standing, which is why basic strategy says to hit 16, when it is 10-6 or 9-7, against a 10). But when your 16 happens to be a pair of 8s, you have an escape: you can split and play each 8 against the 10. Why would you want to do this? Because when you play an 8 against a 10, you stand to win this hand more times ... 38 times, in fact, out of 100 (still a bad hand but better than playing a 16 against a 10). And here’s the key, and what Patrick and others fail to understand:  Playing two hands of 8 against a 10 will lose less money than playing one hand of 16 against a 10. Can I repeat that again ... it’s cheaper to play an 8 against a 10 twice than to play the pair of 8s against a 10 once!

 

Wow, that was a bombshell I just dropped, and I’m sure you’re all saying, “Yeah, right Tamburin, now prove it!” So, let’s do it.

 

Let’s first look at hitting or standing on 16 against a 10. If you win 23 hands out of 100, this means you’ll lose 77 hands and have a net loss of 54 hands. So, if you were to bet $10 on each hand, you would wind up with a net loss of $540 after 100 hands. With me?

 

Now let’s look at the scenario of splitting the 8s and playing each 8 against a 10. Here you’ll win 38 hands and lose 62 hands resulting in a net loss of 24 hands. At $10 wagered per hand, your net loss is $240. Double that and your total loss is $480, which is $60 less than hitting or standing. Voilá, I told you so: playing an 8 against a 10 twice (which is what you do when you split 8s) is cheaper than playing a 16 against a 10 only once!

 

The fourth playing option that Patrick proposed is to surrender the hand. The arithmetic of surrender is pretty easy:  you automatically lose half your bet on every hand. So, after 100 hands, your net loss if you surrendered the 8s all the time would be $500; therefore, Patrick’s option costs you $20 more than splitting.

 

So let’s summarize the losses after 100 hands for each playing option:

 

  1. If you hit, you’ll lose on average $540.
  2. If you stand, you’ll lose on average $540.
  3. If you surrender, you’ll lose exactly $500.
  4. If you split, you’ll lose on average only $480.

 

It’s clear that no matter what strategy you use, you are going to lose money when you hold 8s against a 10. But ... here’s the key ... you’ll save more money in the long run if you split.

 

I know that every once in a while you are going to lose both of your split hands and feel lousy about it (been there, done that). If it’s any consolation, keep this thought in mind when it occurs: You made the mathematically correct play holding a lousy hand, and in the long run, you’ll wind up with more money in your pocket compared to playing the hand any other way.

 

So now that you’ve read the math-based analysis on how to play a pair of 8s against a 10, are you still going to follow Patrick’s advice and surrender? Or have I convinced you to split? I’m waiting.

 

(Note: For the purists who are reading this, there are, in fact, a few rare games where surrendering 8s against a 10 is the mathematically correct play, and that’s in 2-, 4-, 6- and 8-deck games where the rules specify that the dealer must hit soft 17 and double-down after pair splitting is not allowed. But these are terrible games that you shouldn’t be playing in the first place. In all other games, splitting 8s against the 10 is the best strategy.)