37 ( +1 | -1 ) Black'sposition is completely lost; with his king in the center, he's threatened by either Rxe6+ or Rxc8+ and a quick checkmate. At this point Black has no counterplay (what is there to do?), so he just resigned.
For example: 1... Ra7 2. Qb5 Qxb5 3. Rxc8+ Kd7 4. axb5 Kxc8 5. Kxh2 is an easily won ending, or 1... Bf4 2. Rexe6+ Bxe6 3. Rxe6+ Rxe6 4. Qxe6+ Kf8 5. Qf6+ Ke8, etc., white will eventually mate.