So far in the series on double down strategy I have covered what to do with a hard 9-11 and soft 13-18. In the final part of this series I will now discuss what to do when you have a pair of fives.
As you learned in the series on splitting pairs, you should never split a pair of fives. That is because blackjack basic strategy takes into account the high number of 10-value cards in a deck. There are four different cards with a value of 10 (10, J, Q, K) while there is only one card for each other value. For that reason, the dealer is more likely to have a 10 in the hole than any other card and he and the players are more likely to draw a 10 than any other card.
Taking that into account, splitting a pair of fives is bad for two reasons. First, if you start two hands with a five, if you draw a 10 that gives you hands of 15, which are stiff hands that are likely to bust but not high enough to beat a dealer hand if he doesn’t bust. Another reason not to split a pair of fives is that if you already have 10, taking a hit gives you a good chance of drawing a hand of 20, which can only be beaten by one hand: 21.
Okay, so we’ve established that you shouldn’t split a pair of fives. What should you do then? If the dealer shows a 10 or ace as an up card, you should take a hit. If the dealer shows anything else, you should double down.
The reasoning for this again goes back to the fact that there are more cards with a value of 10 than any other value. Therefore, if you double down and take one extra card, you have a good chance of drawing a 20. If the dealer shows a two through a nine, he has a good chance of having a hand of 12-19. All of those hands would lose to your 20. Since you are likely to have a hand that the dealer can’t beat in that situation, doubling your wager is a good idea.
However, if the dealer has a 10 or an ace, he likely has a hand that even a 20 can’t beat. In either case, he could have a hand of 21. If he shows a 10, he could have a hand of 20, which would be a push against your hand if you also have a 20. For these reasons, it’s best to simply hit rather than doubling your hand.