This position was taken from On the Origins of Good Moves, the outstanding new book by Dutch IM Willy Hendriks: my review will be published very shortly.

In Hendriks-Hoffman (Groningen 2007) White won a pawn with 16. Nxd6+! Qxd6 17. Bxa6 Rxa6 18. dxe5 Qxd1 19. Rexd1!, the point being that 19…Nxe4 loses to 20. Rb8+! Nxd8 21. Rd8# – as played (as some of my readers noticed) by Morphy in the opera house.