[jwvdcw]

I know you said not to explain, but other people have already started to, so I guess I will as well.....

Knowing that the guy behind you has the straight, you know that the pot will be raised when it gets to him.

In a tourney, you don't want to take chances, and you sometimes have to pass up small +EV opportunities. Therefore, you strategy should be to get the flush draw to fold. However, obviously, you can get money out of him by betting, having him call, and then getting the other guy to raise him out(or you re raise him out).

So the question becomes: What is the maximum amount that the guy with the flush draw will call?

I think there is a very important concept that you are totally leaving out, however. You mention that you are "almost sure" that the opponent on your right has a straight. Well, the question that arises is one of very high level poker thinking: Do you think your other opponent also has the same read on your opponent as you do? This is vital because if the diamond draw also puts him on a straight, then he may realize that by calling your raise, he is going to then be re raised by the other guy, and therefore he should simply fold to save money.

Against a very good player, I think the minimum raise will be all you are able to get from him. Against a merely 'good' player, you may be able to get away with a moderate amount. I know that you said he was a good player, but thats a very broad discription of his style and skill level, and it is vital to know more here. Does he often chase small bets early on for the chance of making a huge score? This is an important question.

Let us take a look at it from the flush draw's perspective. He has about a little better than a 20% chance of making his flush. With $900 in the pot, a bet or $400 called by 2 people would make it putting in $400 to win $1700, which when you figure in implied odds is an easy call. Obviously now, he might realize that the other guy may re raise if he puts him on a straight as you do, but I think that since he is getting such good implied odds, he will take that risk(unless he was 100% sure that that the initial bettor had a straight). Your other option of $700 seems to be too much. That would mean calling $700 with $2300 in the pot(after the call by the opponent). If the flush comes out, your hand is going to be quite obvious if you have it, so you're not going to be able to get called by a huge bet on the river. Therefore, I don't think $2300 is enough to call a $700 bet even if you were sure that the first bettor won't reraise, which you aren't.

It is clearly the minimum raise that is the best move imo. Perhaps you can raise $300 instead of $200 if you feel like it, but thats about all you can get away with imo.

One last consideration is that it is possible for someone to have both the straight and a flush draw, in which case you are in big trouble. You totally fail to mention this aspect, but it absolutely must be considered.