Now, what are the chances that the text book BxRP sac will occur in your games? They do come up, but I'd say rare. Many players will not allow it to happen, but my opponent in the penultimate round of the 2010 Liberty Bell tournament in Philadelphia did. There was an exchange right before this position came up : 9. e5 N(f3)d5 10. N(c3)d5 ed5. So, move eleven, I had to be sure this sac would work. I needed to win this and the next game to be in contention for a cash prize. It looked to me that all the prerequisites were all in place, and so after at least a 5-minute think I went for 11. Bh7+. My opponent refused the sac with 11...Kf8 and off we went into the game that I ultimately won. But, let's take a look at what could have been. After 11. Bh7+ Kh7, then 12. Ng5+ Kg8 13. Qh5 and here the variation tree forks a bit.

If, 13...Re7, then 14. Qh7+ Kf8 15. Qh8#. The same thing would occur if black played 13...Qe7 or 13...g6.

In my calculations, what concerned me the most was 13...f6 and I had to be sure that the move wouldn't work for Black. So, here is what I saw: 13....f6 14. Qh7+ Kf8 15. Qh8+ Ke7 16. Qg7#. Everything was forced.

There was also 13...Rf6 14. Qf7+ Kh8 15. Qh5+ Rh6 16. Nf7+ and white is having a field day. Black chose the right move, or the lesser evil, when he played 11...Kf8.