Home >> Poker Strategy >> A Good Semi-Bluff Gone Bad. (Or ...

A Good Semi-Bluff Gone Bad. (Or the other way around).

This article is about a pretty common situation that comes up in NL ring – when you make a move with a draw or some kind of semi-bluff and get played back at with an all in from your opponent. Dan Harrington describes a great system for dealing with these kind of situations in tournaments – Structured Hand Analysis.

Dan’s approach is far more in-depth than what we’ll use for this article, and I, as always, strongly reccomend his books. We’re going to run through an example that offers a quick and dirty version of Dan’s model that you can use at the table [with a little practice] to help you decide whether or not to call the all in.

First of all, I saw my opponent do this a few hands earlier.

No Limit Holdem Ring game
Blinds: $2/$4
9 players

Stack sizes:
UTG: $182.80
UTG+1: $246
MP1: $317.82
MP2: $411.30
MP3: $495
CO: $708.50
Button: $90.50
VILLIAN: $392
max_pot: $490.98

Pre-flop: (9 players) max_pot is BB with 6c 4h
UTG folds, UTG+1 raises to $8, 5 folds, VILLIAN raises to $25, max_pot folds, UTG+1 calls $17 (pot was $35).

Flop: 6d 8h ah ($54, 2 players)
VILLIAN checks, UTG+1 bets $20, VILLIAN raises to $40, UTG+1 calls $20 (pot was $114).

Turn: as ($134, 2 players)
VILLIAN checks, UTG+1 bets $30, VILLIAN calls $30 (pot was $164).

River: 8d ($194, 2 players)
VILLIAN checks, UTG+1 bets $60, VILLIAN folds.
Uncalled bets: $60 returned to UTG+1.

Results:
Final pot: $194

Then came this hand. I hadn’t been raising very much at all preflop and decided to try and pick up the button and maybe the pot.

No Limit Holdem Ring game
Blinds: $2/$4
8 players

Stack sizes:
UTG: $726.70
UTG+1: $90.50
VILLIAN: $297
max_pot: $470.98
CO: $182.80
Button: $345.50
SB: $407.30
BB: $491

Pre-flop: (8 players) max_pot is MP2 with 6s 8s
2 folds, VILLIAN calls $4 (pot was $6), max_pot raises to $17, 4 folds, VILLIAN calls $13 (pot was $27).

Flop: 9h 9d 7c ($40, 2 players)
VILLIAN checks, max_pot bets $30, VILLIAN raises to $60,

I saw a repeat of the behavior from the previous hand [the dink CR bluff] – I thought it was likely that he was putting me on AK and trying to represent the 9. I decided to clarify my hand for my opponent and raised, trying to communicate that I had an overpair.

max_pot raises to $155,

Then it got a little sticky.

VILLIAN raises all-in $280,

At this point it wasn’t really relevant any more what hand I was ‘representing’ – now the hand shifted to a cold calculation of whether or not I had the odds to call. It’s hands like this that sort of make me hate playing online – give me an extra minute and I can make a much better decision.

I had to call $155 more at this point for a $445 pot. I was pretty damn sure he didn’t have a 9 – I put him on an underpair, a 7, or maybe 10 10 – I figured there was also a small chance that he was just on 2 overs. Here’s how I asses of the likelihood of each hand:

Underpair: 20%
Seven: 50%
Overpair: 5%
Overs with no draw: 10%
Overs with gutshot / redraws: 15%

Note that these estimates are obviously backward looking and possibly skewed, but what I haven’t yet done is calculate my chances against each hand, so I’m not ‘fixing’ the estimates to get me the conclusion I want. I’m not sure that this was a good call yet, although I’m leaning that way. [Note: I can hear you. How can I be so sure he’s not holding a nine? You’ll find an alternate set of numbers below that attempt to satisfy that question]

That’s right, I called. It’s a little under 3-1.

max_pot calls $155 (pot was $445).

Turn: tc ($600, 1 player + 1 all-in – Main pot: $600)
River: th ($600, 1 player + 1 all-in – Main pot: $600)

Great turn, terrible river, but it worked out. This time, anyhow.

Results:
Final pot: $600
MP1 balance 0 lost 297 5d 5h
max_pot balance 770.98 bet 297 collected 597 net 300 6s 8s

Now how about that math? I don’t think my estimates for his holdings are all that crazy, so let’s see how it breaks down.

Underpair: 20% – Against 55 I win about 42% of the time, any lower I win about 53%
Seven: 50% – Here I win about 36% of the time against A7, win about 25% against 78, win about 40% against 76. My worst case scenario is that I’m a 3-1 dog.
Overpair: 5%. If I’m up against 10 10, I’m in trouble at 16%; against QQ I win about 30%.
Overs with no draw: 10%. I’m about even money here to KQ, AJ etc
Overs with gutshot / redraws: 15% – I’m thinking like J10; I’m about 35% to win.

The loose conclusions is that since I’m almost always better than 3-1, I have to call. Here’s my scrub math

20% [Win $445 44%, lose $155 56% / W = 195.8 L = 86.80] +109 = 21.8
50% [Win $445 33%, lose $155 67% / W= 146.85 L = 103.85] +51.82 = 25.9
5% [Win $445 20%, lose $155 80% / W = 89 L = 124] – 35 = -1.75
10% [Win $445 50%, lose $155 50% / W = 222.5 L = 77.50] +148 = 14.8
15% [Win $445 35%, lose $155 65% / W = 155 L = 100] +55 = 8.25

Looks like a positive expectation of about $69.

How certain would I have to be that he had a nine to fold? Let’s swap out one of my best situations – an underpair – for A 9. I’m still going to argue that there’s a very slim chance that my opponent is holding the nine based on how the hand played out, but I’m curious. I’m about a 3-1 dog to A9, J9 and 98; the worst case scenario is about 7-1 if he’s holding 10 9. Let’s call me 4-1

20% [Win $445 20%, lose $155 80% / W = 89 L = 124] +109 = -35
50% [Win $445 33%, lose $155 67% / W= 146.85 L = 103.85] +51.82 = 25.9
5% [Win $445 20%, lose $155 80% / W = 89 L = 124] – 35 = -1.75
10% [Win $445 50%, lose $155 50% / W = 222.5 L = 77.50] +148 = 14.8
15% [Win $445 35%, lose $155 65% / W = 155 L = 100] +55 = 8.25

That cuts down my expectation to about $13. Still positive. If I swap out the overcards with a scenario where I’m drawing dead, that swings it to about a -$20.

To put it very roughly, I’d have to assume that he’s holding a nine or stronger almost 30% of the time to make a fold correct here.

I’m a little surprised by this conclusion; maybe I did the math wrong somewhere. The call seemed a lot more borderline to me at the time, but it looks pretty automatic in the review. And that’s the moral of the story – this hand is just another example of how one or two seemingly harmless assumptions about ‘correct’ play – especially when calling all ins – can be eating away at your bottom line without you even knowing it.

Get your daily dose of poker news with the PTP Hit and Run.

Exclusive Freerolls and up to 60% cashback at Carbon Poker >>>