Playing marginal hands sometimes

[Kurn]

First of all, T9s is not marginal to play in LP for one bet. That part is fine.

On the flop, how many people are in the pot? Where did the bet come from? How large is the pot? The answers to these questions determine your action. If the pot is small you fold. If the pot is large (8 or more bets) and the bet has been called befor it gets to you, call. If the pot is large and the bet came from your immediate right, raise.

Like all poker situations, the right answer is - it depends.