Not all casinos allow Mississippi Straddle. A Mississippi straddle will allow a player to post a straddle from any position, but most likely from the button, which is the best position to post. Different casinos have different rules. Some casinos will let a player only post from the button position and others from any position. Casinos also differ from where the action begins from the straddle. For example: when you post a straddle on the button, some casinos put the action on the small blind. Other casinos will put the action on the seat left of the big blind or the Under the Gun (UTG) seat. Now , if you are seated to the right of your target (your target is in the small blind or the big blind), you can go after him with a straddle, if it is likely few other players will call behind him if he is first or second to act. In any situation, you have good position to raise with anything reasonable even when a limper or two enter the pot. If the pot is min raised, you should 3-bet with anything reasonable. If it is a normal raise to you, access the raisers range and you could 3-bet if you believe the raiser is making a play. Fold to a tight player and call if you have a reasonable playing hand that is offering good implied odds if you hit your hand on the flop (small pairs and suited connectors). Also, if the target is likely to call the raise, then play more often, even with weaker hands like J8, Q9, and 87.
When the action falls on the UTG seat, and the UTG is your target, you occasionally straddle from the button when target is limping with lots and a straddle doesn't make a difference to him. Again, if there are limpers after your target enters the pot, raise with anything reasonable--and make your raise big. You have great position and you need to isolate your target.
Example of Mississippi Straddle: The game is $1-$2 no-limit Hold'em. Your target is the UTG seat with a stack of $500. You are on the button with $300 and you straddle to $4. The action is on the UTG. He calls. Two others limp. There is $19 in the pot. You have K9. It is not a very good hand, but you have great position, so, you raise to $35. Everyone folds.
This time, the only player is your target. You have 9♦ 5♦. Will a raise push out the small and big blind? This is a question you'll have to ask yourself? Many players are serious about defending their blinds especially the big blinds. So, you make a good sized raise to $30. Both blinds fold. Your target calls.
Flop: 7♦ A♦ T♠
Your target checks. You have a decent flop: flush draw, backdoor straight draw, and the A is a good bluff card. You bet $40. He thinks for a while, then calls.
Target checks. There is $140 in the pot. You bet $100. He turns over KJ and folds.
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