This question is taken from the
Donkey Test website, and is
being discussed in the Beginner's Forum.
I think a good case can be made either way, but I lean more toward a fold here based on what I recently read in NLHTAP. Here is what my response was in the other thread:
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I answered "fold" on this one, but thought I might be wrong, so I looked it up. I don't understand the math behind this, but if you read the end of NLHTAP you will find a chart that answers this question. The pertinent information is that you are having to call $8k to a heads-up all-in with a pot of $13k. You are getting just a tad over 3:2 pot odds, so it is wrong to call if the all-in player is pushing with much better than any 2 cards.
Specifically, DS says it is wrong to call with T5o getting 3:2 on your money if your opponent is pushing with: AA-22, AK-A2, Any two cards 7 or higher (e.g. T7), K6-K4, and K3s-K2s
If he is pushing with a lot more than that (any two cards), then you can call.
I don't think the CO would be pushing with much less than that, since they have just passed the blinds and can afford to wait a few hands for a better hand to push with.