Chess Puzzle of the Week (77): Solution

puzzle77

Last week I left you with this mate in 2 from FFL Alexander (1911).

White has a set mate for every Black move but is unable to maintain the status quo.

The solution is 1. Rb2, threatening Rd2#. 1… Ke5, Nc6 and Nb5 are all met with 2. R(x)b5#.