Hi! I was reviewing a hand recently and I got confused about what blockers are good to have in certain situations. The following hand is an example hand that illustrates what I'm talking about a little better.

150BB effective stacks 6-max cash game

Hero (BU) gets dealt QJ

CO opens to 3BB
Hero 3bets to 9BB
CO flats

Flop (19.5BB): 277
CO Checks
Hero bets 6BB
CO Calls

Turn (31.5BB): 5
CO Checks

Now here is where I get confused. Is this a good spot for an OB?

Yes - We don't block the FD's in his range and if we OB he is not getting the right price to continue with these hands. Also since these hands have more SDV making them fold is a big win.

No - We don't block the FD's in his range and if we OB he is still getting a good price to continue with these hands.

Or is it perhaps a mix for some reason?

This flop favors you as the PF 3-bettor in that you have lot's of medium to high pairs, lots of Aces and Kings. and some flush draws in your range. You probably also have 2 suited A7's, pkt 2's and 1 combo of pkt 7's for nutted combo's.

Even though you have range advantage, I think CO has nut advantage because he has more 87s and 76s type hands in addition to the the same pkt 2's, pkt 7's, A7s, flush draws, and over-cards to the 7's that are in your range.

Even though you have a good range board, your actual hand whiffed the flop. All you have is 2 overs. I think that range advantage plus the potential to get a worse hand to fold are a good reasons to bet. Since the board is actually pretty dry, I think the villain will tend to be a bit sticky and therefore the flop bet needs be on the larger side.

As far as blockers go, you want to not block villain's bluffs/draws and block value, so not blocking diamonds of the flop is good, and not blocking spades on the turn is good. You also do block a few combo's of good hands that he could have like AK, AQ, AJ, KQ, KJ, JT etc, so that is all good.

Just remember that blocker effects can change from street to street. If a flush comes in, then all of a sudden you would want to be blocking flushes instead of not blocking them.

I think I have to agree with your idea for an overbet on the turn, but no reason to get carried away with size because if he has a 7 he is never going away. Maybe pot sized bet on turn. You can fold out hands that have equity against you, and even fold out some hands that are ahead that have higher overcards to the board than your hand.

Your blocker logic is correct. Since villain can't hold Qc/Jc they are more likely to hold a flush draw, or perhaps a lower pocket pair.

The way they choose to play their FD is up to them. In some cases you prob even want them to call with their FD's. All the blocker effect tells you is that they are slightly more likely to have a FD- anything after that stems from your assumptions about their play.

I don't think an overbet is the correct play in this scenario though. CO's range is likely super tight at this point, and they prob have the nut advantage in trips. Your target isn't really FD's, your target is more like middling pocket pairs. Bet an amount that make those medium strength hands uncomfortable, without getting stacked by their trips.

Thank you both for the response.

Yeah maybe my flop choice was a bit flawed. Probably 332t would have been a better choice as neither of us has many (if any) 3x, but the BU has all the best overpairs.

As far as my blocker question I think my perspective on this topic at the time was a bit flawed, as we don't know if V wants to continue with his FD's or not.

What we should be focussing on (I think), is what part of his range we want to put PRESSURE on. In this hand that range consists of medium pairs like Tombos said so 66, 88-JJ and his FD's + Overcards. Since we unblock a lot of that range when we don't have a FD I think this is a good hand to bet with.

And yeah I don't think an OB makes much sense here since the CO definetly is going to have a good amount of 7x (maybe even more).

Just few rules(not strict)
-bloker effects are most important on the river or on some earlier streets if ranges are narrow. They can be deciding factor if two lines are close but you won't lose much of EV if you make that kind of mistake
-You should use ob if your opponents range is capped and stacks are deep in comparison to pot. Generally polarized range wants to bet same fraction of the pot on every street, so if you can get all by the river without ob you should to that. That is reason why ob os not often a move in 3b pots.

Btw about hand we can pretty much can ignor 7x in CO there is only few of them to begin with and after flop xc there is close to 0 7x in his range.

Thanks, yeah I think focussing too much on blockers is a bit of a leak of mine (among many haha) so I think your first point is definetly valid. I think I do this because it's the only leverage of information we have aside of villians actions. Blockers are definetly important, but I think a better framework to think about blockers is what hands do we want to block and not, what are we blocking right now, because that way it becomes way easier to level yourself.

I'll have to do some research on sizing in 3b and 4b pots then. Betting small here for the same size for three streets with a polarized range seems kind of unintuitive to me.
Do you have any articles on bet-sizing in 3b/4b pots?

You have proof for that in mathematics of poker for nut and air type of rage, in real poker there are other factors that can change betting structure.

Cool thanks, I'll do some research to see if I can find an upswing article myself aswell.

Btw you can do it yourself if you know calculus. Do it for two sreets, assume you bet B1 on first and B2 on second with hand that always wines at SD then assume that opponent is calling mdf(P/(P+B) where P is size of the pot). Write down EV function and see what is maximum of that function under the condition B1+B2=S, where S is effective stack size.

Thanks, I'll give it a go when I have some more time.

From that statement it seems you are thinking about it the wrong way. It really doesn't matter whether a pot is 3b or 4b per se.

The two things that matter are how ranges are affected due to 3b/4b, and how the PF bet sizing affects SPR (stack to pot ratio) and those are the two things that you need to study for 3b/4b pots just the same as any other pot.

3b's/4b's are designed to indicate strength, and from an optimal player this strong range will also include some bluffs for balance. Your task playing against them is to piece together their ranges as best you can by factoring in clues such as bet size, player type, and what positions the bets are being made from. If an UTG player makes a 4b against an UTG+1 3b, that is in general a different consideration than if CO makes a 4b against BTN 3b, etc.

So these bigger bet sizes refine player hand ranges, reduce the amount of chips remaining in player stacks, and increase the pot size. When the flop comes down that's what you should be thinking of (not whether it is a 3b or 4b pot). You should be asking yourself how the flop texture interacts with each player's PF ranges, whose range has nut advantage, how does SPR affect betting, how my actual hand fits in my perceived range, how much equity does this hand have and how robust is the equity, what hands am I targeting, etc. etc. In other words, just relax and consider all the normal things you would in every other pot you are in.

Yeah you're right that there's no 1 good betsize in 3b or 4b pots, but I'm just looking for something that outlines some general guidelines in c-betting in these situations. Maybe there are some examples alongside with it.

Like in this spot we c-bet for a 1/2pot bet because...

Where as in this spot we c-bet for 1/4pot because...

So just checking if I'm doing this correctly.

EV of betting two streets = (1 - MDF1)*EV(bet street 1 and V folds (1F)) + MDF1*EV(bet street 1 and V calls (1C))

EV(1C) = (1 - MDF2)*EV(2F) + MDF2*EV(2C)

EV = P*B1/(P + B1) + (P/(P + B1)) * ( (B2*(P + 2*B1))/(P + 2*B1 + B2) +
((P + B2)/(P + 2*B1 + B2)) * (P + 2*B1 + B2) )

Then go from there?

Bit messy but looks good at first glance. Use B2=S-B1 and then find maximum( find at what point derivative is equal to zero).

Ah right thats a good substitution.

Alright this is pretty frustrating lol. I've finished my calculus courses at uni with good grades. My solution is very long and complicated, this usually indicates that something went wrong, so again I'm just checking.

So we're looking for an expression of B1. How simple does this expression look like?

Right now my solution contains a giant squareroot and all kinds of exponents. Also it looks really ugly.

Are you certain the above expression is correct?

Substituting and simplifying yields:

(P/(P + B1)) * ( (((S - B) * (P + 2*B1)) / (P + S + B1)) + P + S)

Looks okay-ish to me, but it's pretty horrendous when I try to take the derivative.

You can always plot it for a specific case.

Yeah good point, I'm just wondering if I did anything wrong.

And as I have found a solution where B1 is expressed into P & S I could also just make P constant (P = 1 for example) and then we can graph B1 for different effective stack sizes.

You should get something like B1/P=B2/(P+2B2), but i wouldn't waste too much time getting to that result.

Important thing is that a perfectly polarized range will bet same bet sizes(compared to the pot) on every street.
Obv he picks sizing which allows him to put whole stack otr.

Thank you, though shouldn't the result be B1/P = B2/(P + 2*B1)?

flop you want to bet bigger because of the advantage in the top of your ranges
ap we are looking to ob this turn since that advantage follows you on non board changing cards, but these combos won't always make it in that range