An Interesting Gap in Jacks or Better

Let's examine a common gap in good old jacks or better. Assume you are playing 9-6 jacks (i.e., you receive 9 for a full house and 6 for a flush), and you could choose between either of the following hands. Which would you choose, and how would you play it?

The only difference between the hands is in the club straight flush draw. The 235 has an obvious gap in it --- that is, it is missing the 4. The 234 has no such obvious gap --- that is, the cards are right next to each other.

If you have a chart which tells you this information --- great. I'm all for tools to make life simpler. Similarly, many of you have these combinations memorized. Great again! A good memory is helpful in video poker. But let's assume that you either don't have a chart handy, or you don't trust your memory on this particular combination. What do you do now?

The only differences between the 235 and 234 combinations will be straights and straight flushes. Drawing two cards, neither combination is better than the other is when it comes to getting high pairs, two pairs, trips, or regular flushes. And when it comes to full houses, four of a kinds and royal flushes, you're equally up a tree from either starting position.

Let's simplify and look only at straight flushes --- that is, assume we draw clubs.

There are two perfect combinations starting from 234, and two perfect combinations from 235. The conclusion, then, is that 234 and 235 are equivalent combinations. This is surprising when you first encounter it. How can a "no-gapper" like 234 have the same value as a "one-gapper"? The explanation doesn't concern the gap in 235. It is very real and affects the value of the combination. The explanation comes from the fact that the 234 combination "runs into the ace". If you look at a legitimate "no-gapper" such as 789, you'll see there are three 2-card combinations that will complete the straight. You have the "two cards below" combination (in this case 56), you'll have the "straddle" combination (in this case 6T), and you'll have the "two cards above" (in this case TJ).

Look again at the 234 combination. The two combinations we have fit the "straddle" and the "two cards above" categories. You'll see we don't have room for the "two cards below" draw. With only two different perfect draws, it is fair to consider the 234 combination as belonging to the "one-gapper" family. The better strategy charts tell you to include 234 with the one-gappers. Although figuring this out isn't real difficult, as we've seen today, it is an easy combination to forget.

Now for the second part of the question. How do you play the hand? Knowing that a suited 234 is equivalent to a suited 235 is one thing. Knowing whether it is higher or lower than KQ of different suits is another.

It turns out that going for the straight flush combination is quite a bit higher than holding the KQ --- almost 20¢ when you're playing for dollars. Even if we started with an unsuited QJ, which has more straight possibilities than does KQ, 234 or 235 would still be the superior play by 12¢.

I believe that straight flushes are the least understood hand in video poker. We will revisit this subject many times in the future, although not for a while. These discussions tend to be more technical than many of my readers prefer.

That's it for this time. Until next time, go out and hit a royal flush.