Rook Queen Rook Checkmate

I won this club-based tournament correspondence chess game a few hours ago playing Black when I caught the White King in a Rook, Queen, Rook Checkmate. The above graphic image shows position of pieces at game's end. You can see my G1 Rook delivering the mating move. The White King's only possible flight squares were covered by my Queen at C4 and my other Rook at D8.
The full move record of this game: 1. e4 a6 2. d4 h6 3. Nf3 d6 4. Nc3 Nf6 5. Bc4 Nc6 6. O-O Be6 7. Qd3 Bxc4 8. Qxc4 Na5 9. Qa4+ Nc6 10. d5 b5 11. Qb3 Na5 12. Qb4 c6 13. dxc6 Nxc6 14. Qb3 e5 15.Ng5 hxg5 16. Bxg5 Rh5 17. Bxf6 Qxf6 18. Nxb5 Nd4 19. Qd5 Rc8 20. Qb7 Qe6 21.Rad1 Nxb5 22. Qxa6 Nc7 23. Qb7 f6 24. Qc6+ Kf7 25. c4 g6 26. Rxd6 Bxd6 27. Rd1 Rd8 28. c5 Be7 29. g4 Rh4 30. Qxc7 Rxg4+ 31. Kf1 Qc4+ 32. Ke1 Rg1# 0-1
And the adventure continues.
posted by Roscoe