Raising the flop to force out the third player is unlikely to succeed unless MP is drawing virtually dead because 1) the pot is very large and 2) his opponents are "two cards" and "person trying to get HU with two cards". SB has no credibility and because of that neither do you.

It is better to call the flop and raise the turn. Based on OP's description of SB it seems pretty certain that he will bet again even with nothing. Now the raise gives us maximum value for our equity advantage and much better leverage to remove MP from the pot.

protecting on the turn is infinitely better than not protecting at all. now that i re-read Mg's post i see that he doesnt rule out that possibility. i would still make some counterpoints: hero's range is not "trying to get hu w 2 cards", its quite strong due to preflop action. MP might not realize the dynamic of SB. even if he does realize it, he's still folding Ax,Qx, which we want him to do particularly when he has backdoors. hell, in MPs spot, i'd strongly consider folding 8x/5x.

I think MP folding a split pair for two bets is a really bad idea. Possible best hand with five outs in a big pot. Folding an eight is virtually tantamount to saying you need top pair to play (because A8 has better equity than TT) and people will push you off a lot of pots if they figure that out.

I really don't care very much if MP tags along with Ax:

1. We might be chasing SB anyway.

2. When we are ahead SB is very likely to have his own Ax (see OP's notes). Now we would love for MP to stay in with a counterfeit hand.

MP calling one bet approximately compensates us for the risk of letting him see the turn.

put me in the call flop camp

Im not saying it is a clear call by any stretch, but imo raising for "protection" is a too overrated of a play in spots like this one.

At what pot size, if any, would you be inclined to raise the flop?

I think you have enough equity that the hand is worth a raise. The question is when is the best time to do it.

The normal answer is *now*. Waiting is dangerous because SB is likely to get two callers and decide not to bet anymore. Then I wind up never getting to raise. Even worse, SB may bet good hands and check bad ones. Now I only get to raise when I am losing .

For this hand I am making an opponent-specific assumption (based on OP) that SB will nearly always continuation bet the turn. That allows me to make the exploitative play of going for a double-size raise on the turn.

Pot size does not affect this argument very much. If the pot were small enough we wouldn't be worth a raise at all. Otherwise pot size matters only if it affects the way my opponents play. Which is a question with no obvious answer.

agree that people often overrate protection. however, given the read and preflop action this is a fistpump raise for protection and value at some point in the hand. since the pot is big enough that we want something with as little as 3 outs to fold, i cant see how waiting is possibly better.