Poker Strategy: Chasing a Flush Online

There are a few questions which come up regularly, and we try to provide easy-to-follow and useful answers. Many amateurs have recently written in because they want to know if they should ever chase flushes when playing online, and if so, when is it a good idea. In order to proceed, we need to first define what is meant by the term “chasing a flush”.
When you chase something in Texas Hold’em you are typically one card away from a strong hand, so you bite the bullet and hope for a hit on the turn or the river. You know it’s a risk, but you are prepared to commit to the hand and hope that the cards turn in your favor. It’s just another aspect of poker which makes it such an intriguing game. Occasionally, you must rely on a bit of luck if you are going to win.
For example, let’s say you are dealt the Ace and 4 of diamonds and the flop comes out as 6d 9d Qs. Most of your opponents fold when the first to act opens the betting with a big raise. At this point you know that one more diamond will give you the nut flush, but you still aren’t sure if you want to risk it.
You first need to consider what your opponent might be holding. The main possibilities include a set of trips, two pairs, a pair of Queens, and of course he may be holding out for the flush draw as well. Also he may be just bluffing and trying to steal the blinds. Since you are holding the Ace, you know that if you hit one of your diamonds and make the flush, then the only hands that can beat you are a full house and four-of-a-kind (both of which would require a bit of help on the turn or river as well). If you get that additional diamond you stand a pretty good chance of winning the hand.
So now you need to consider the odds of getting your card. You assume there’s about a 50-50 chance of getting it, since there are 2 more cards to see and only four suits in total. This is where you are making a mistake, however.
Think about it. There are 13 cards of any one suit in a deck. You have seen 5 of these 52 cards, and 4 of them are diamonds. This means that 9 of the remaining 47 unseen (by you) cards are diamonds. Thus you have a 9/47 (19.1%) chance of hitting your card on the turn and a 9/46 chance (19.6%) on the river, giving you a 38.7% chance of putting that beautiful flush together.
Of course in order to see the turn or the river, you will need to put even more money into the pot. So this is where you need to consider the pot odds and whether or not it is worth the risk. How big is that pot? Is it really worth depleting your chip stack in the event of a failed draw? What about your opponent’s chip stack? Is he merely bullying into folding?
Remember, my example scenario from above is a bit easier to consider. Perhaps in reality you aren’t holding an Ace, and therefore the nut flush isn’t necessarily yours. This is why the risks of chasing flushes are seldom worth it. Even despite the numbers, think about how often you have actually put together that winning flush.
Poker is certainly about making the right choices, but it’s also about getting lucky. You can’t win without taking risks, but you can measure the risks and then decide if they are worth taking. As a self-professed tight-aggressive player, I seldom chase the flush, but that doesn’t mean I’ve never been burned by someone who does.