Andy Murray beat Japan’s Kei Nishikori in a gripping contest to secure victory for defending champions Great Britain in the Davis Cup first round.

The Scot won 7-5 7-6 (8-6) 3-6 4-6 6-3 after four hours and 54 minutes to give the hosts an unassailable 3-1 lead in the best-of-five tie in Birmingham.

Murray, 28, won three matches in three days in his first event back following the birth of his daughter Sophia.