Defending the blinds is basically calling a raise with less money. So if you have a drawing hand in a 2/4 game on the big blind and the pot is raised to 2 bets, 3 callers, there is 15$ in the pot (4x3 + sb + bb). Now you would be able to get in on the action for 2$, as you have posted the blind already, i.e. you get to see a discounted flop: This doubles your pot odds, instead of 4/17 you are only calling 2/17, which is significant. So a drawing hand is something you can defend with (but tighten up if you miss the flop).
Defendant
|