This is my first offering for players new to Omaha strategy. As such it shall be more concise and less challenging than most of my other articles to date. It is not directed at the  mid/high-stakes player although I expect there will still be some points of interest here. I also apologize to William Hughes Mearns, noble poet and fellow alumnus.

The Straight that wasn’t there: turn transitions with a set on a nonotone board

Yesterday, upon the turn,
I saw a straight that wasn’t there
It wasn’t there again today
I wish, I wish that straight away…

When I check-raised to twelve BB
The straight sprang from the deck for me
But when I failed to make the call
I couldn’t see it there at all!
Go away, go away, don’t you come back any more!
Go away, go away, and please don’t call the floor… (call!)

Last night I saw upon the stair
A sucker straight that wasn’t there
It wasn’t there again today
Oh, how I wish that straight away

Our opponent raises from the CO, and it folds to us in the BB, we call with AJJ3 single-suited to the Ace. The flop comes down J92r and we check, face a bet of 5BB into 7.5BB, and raise to 17.5BB. Our opponent calls, the pot is 42.5BB going to the turn with 79BB behind. What turn transitions are there, how do they affect our respective ranges, and how should we play accordingly?

Of the 45 unseen cards, we still have the effective nuts on 25, with the board straightening on 20. So if you are one of those players who still says, “F*ck,” when a straight hits on this type of board your first leak to plug is a mental one. Boards change in Omaha, and you should expect this board to change close to half the time when you have the nuts, so deal with it. The 20 straightening cards are four each of {K,Q,T,8,7}. Only 4 of these will keep the board nonotone, the other 16 will bring a flush draw

1.

Pseudo-danger cards

The Ten here is a ‘pseudo-danger card’ insomuch as it is such an obvious straight card that many players will freeze on sight, check-calling turn and then sigh check-folding when their rescue boat doesn’t sail in on the river. In reality, however, the ten does not complete any open-ended straight draws. Since OESDs are far more common than wraps, they will comprise a far greater portion of your opponent’s range (be sensible, this obviously does not apply to huge nits) than do wraps. 100BB deep, I suggest treating running into a wrap here as a ‘cooler’ until a player proves otherwise, since the money was destined to go in anyway and it is more important to play well against the non-wrap part of your opponent’s range. The ten only completes 3 gut-shots: the 87 (which you will only run into against very loose players), the Q8 (mostly AQJ8,  AAQ8 ,KKQ8,QQ8x) and the KQ (AAKQ, KKQx, KQJx, many more against fish). On all the two-toning tens you should be bet/calling or CRAI depending on how frequently your opponent will stab here when you check. Your opponent will make far too many two pair + FD, OESD + FD for you to even consider a line with calling/folding in it. The nonotone ten is an exception, I would recommend half-pot/folding against most straightforward players since they represent only a straight and need to be extremely confident that you will fold to make a 0 equity bluff (They need you to fold over 55% of the time, and if your CR flop range now has some straights in it, which it should, they are going to be in difficulty). Against very loose players, checking is the clear choice, since they won’t be able to help themselves by stabbing. You can CRAI or check-call/check-call depending on their tendencies. I do not recommend cc/cf river against this player type.

The ‘pseudo-danger’ middle turn is a common feature on other boards in this family: {J9x,T8x,97x}. Be careful on QTx against tighter ranges, since your opponent’s range is full of AKxx which he will be loth to fold for a single CR. Also be wary on low boards, where hands with the nut-gutter are far more likely to float you on the flop since a set is such a small part of your perceived range.

Caution cards

The Q and 7 are more dangerous than the T, but have a number of mitigating factors which render them less of a threat than they first appear. Since they both complete the T8xx OESD2, one should consider how this hand fits into our opponent’s range and how it is perceived. For a start, there are as many T8xx in a tight opening range as there are in a loose range. For reference, around 7% of hands in the top 15% of hands contain a T8 combination, and 7% of a ‘playable 70%’ range contain this combination. If the board in question were lower or higher, the proximate OESDs would be weighted differently by the width of ranges (This effect can be huge, see for example my advanced post on High lockdown flops). Next, many strong T8xx hands contain a pair, and an aggressive opponent will often shove top/middle pair+OESD over a CR on this board. Most importantly, a thinking player is aware that if he draws to the Q he is drawing to a second-nut hand, which can be extremely costly facing a wrap, top two + gutter type hand. His error can be compounded if you are bluffing and continue your aggression on the turn, where he may make some incorrect folds. If continuing with the naked OESD is only good against a small portion of your range (the sets), he may choose either to fold to the CR, or to check it back in the first place. Since we have drawn the inference that a thinking player will choose not to bet/call many T8xx on the flop, the 7 becomes a lot less scary.

I thus propose that against decent players we should be stacking off on the two-tone and half-pot/folding the nonotone {Q,7} turns as before, expecting the line to be +EV but to a slightly lesser extent than in the ‘pseudo-danger’ turn card situation.

Non-thinking players

Loose recreational players, and undisciplined LAGs whom variance or ego has deceived into believing they are ‘tough regulars’ will call your flop CR with pair+gutter and the weak OESD. Consequently they will hit the straights detailed above with a higher frequency than a more disciplined player. In order to exploit this, it is prudent to examine both how frequently your opponent will be calling your CR, and his EV for calling the CR given a few assumptions.

If our opponent has opened a playable 70% range (this would be relevant OTB or HU rather than in the CO as described) then if he continues with a range of {T8,QT,J9,99,22,J2,92,KQ,AQJ,AKJ,QQ,KK,AA}3he will be continuing with 29/70= 41% of his hands if he C-bets 100%. The nature of his check back range does of course matter, but the loose villain detailed is likely to be betting all of the hands I have put in his bet/call range. If we assume he is C-betting with an 80% frequency, then he calls the check-raise 29/(0.8*56)= 52% of the time. We should avoid check-raising pure air against this opponent, not least because pure air on this board involves cards so unrelated to the flop that our opponent’s continuing frequency will increase.

With his given calling range, we will still have the best hand on the turn for a {Q,T,7} {62,65,77}% of the time respectively. A casual inspection will reveal that if our opponent wishes to fold anything worse than a set on these turn cards then we can check-raise the flop with gut-shots and barrel these 12 cards profitably. As soon as our opponent adds hands weaker than a set to his continuing range, non-straights will comprise more than 50% of his range and we will be able to value bet profitably. Since bet/folding is not an option, we should be willing to stack off on these turn cards against such opponents.

Let us assume the most favourable situation for our opponent calling with bare T8xx for implied odds (neglecting bluffing opportunities for the present), namely that we always have top set when we check-raise, and that we will always stack off on the turn when he hits his straight. The 8 times that he hits, he averages 73% in equity (we sometimes pick up a FD to go with our set) which  means he makes (0.73*200.5)-91.5=  +54.9BB. The times he misses he loses (Size of our check-raise)-(Size of his C-bet)= -12.5BB in the example given. Leaving his side cards as unknown, he loses on 35 of 43 turn cards. His EV on the play is (54.9*8 – 12.5*35)/43=+0.04BB. This is barely profitable, and certainly losing after rake is taken into consideration. Notice if we increase our check-raise to pot, the EV drops to (54.9*8 – 17.5*35)/43= -4BB4. If we add all of the KQT wraps to our check-raise range (for completeness the range I used was {[A-T]jj$ss,KQT$ss,KQT$ds,[A-T]JJ$ds}) then his average turn equity when he ‘hits’ a Q or 7 with T8xx is only 58%. This drops the EV to (25.4*8 – 17.5*35)/43= -9.5BB. Thus it is pretty easy to adjust to a call-happy opponent 100BB deep by check-raising the flop large and for pure value. As I have stated before, optimal lines against such opponents generally revolve around using aggression against his weak range and forcing him to make a hand to beat you.

In short stack off on the turn with top set after check-raising against a loose player, he won’t hit the turn frequently enough to make this play -EV.

Legitimate Danger Cards

The K and the 8 are the worst cards in the deck for your hand, since they complete the most probable OESD: QTxx. Furthermore they comprise 13% of all hands in a tight range (and thus even more of his flop C-bet/call range) although only around 7% of the loose range described above. Accordingly we should likely still be stacking off against the latter, but should strongly consider checking the former. Barring a ridiculously small bet, I would advise against check-calling the turn planning to ‘give up on the river/lead if you boat up’: this is transparent to all but the most obdurate regulars. This suggestion has two notable exceptions:

1) There are regulars in the games stupid enough to bet the turn here with the nut straight and then call off the board pairing on the river when I open pot it. I presume they put me on a gutter/OESD that picked up a flush draw and now decided to play passively(!) Against these players, you can obviously check/call, shove river binks but make sure it is to pot. Getting cute when you hit and betting half pot to “make sure you get value” turns this line from +EV to -EV.

2) Against a player who loves to hero-fold rivers, you can check-call a medium-size turn bet and bluff the river flush cards. This is only profitable when his bet is in the <70% pot range. Do not do this against a pot sized turn bet, you are lighting money on fire against a guy who can fold since he is not paying off your boats.

In summary, on J92r texture flops, not all straight cards are equal. In fact, most do not intersect with your opponents range enough to justify dumping your set. Beware of the K and the 8 against solid players and check-raise big and hold on to your hand against LAGtards.

Until next time,

Quad

I received a number of helpful responses from micro/recreational players last time in my request for feedback. Please keep them coming. If you fall into this category, please let me know whether the article was too hard/too long/just right. Also feel free to suggest topics for future posts. The narrower the specification, the better; I’m not going to solve 3-betting for you in a blog post, but I will help you with ‘flushing rivers in 3bet pots’.

Show 4 footnotes

  1. This is one of the oft-forgotten reasons why having a suit to go with your pair really matters. Increasing by 4 the number of turns where you have an auto-stack off makes a big difference in a game of small equity margins. So if you are one of those players who still set-mines in every multi-way pot, do yourself a favour and drop most of the unsuited hands.
  2. The KTxx gut-shot is dismissed on similar arguments to the above discussion, which is omitted here for the purpose of brevity. This is, at least, brief by my standards!
  3. I may well have missed out a few hands, I am not aiming for a precise range here, merely a quick approximation
  4. For those new to such calculations, losing 4BB on a flop play is a big mistake