The problem that defeated Tal and Spassky

Introduction

German GM Klaus Darga used to stump strong players around the world with this problem. In fact, he's quoted as claiming: “Even Tal and Spassky gave it up after they tried in vain for three-quarters of an hour to work it out.” Can you do better?

The composer left us many beautiful problems and made an important contribution to endgame theory. In this gem, finding White's only winning first move requires thinking way ahead to the final steps of a race.

The Problem

J. Vančura, 1922

White to move and win.

(Solution appears below.)

The Solution

Outro

For more on the wonderland of chess problem compositions, visit ChessProblem.net.