Jannik Sinner ruthlessly ended Novak Djokovic’s latest bid for Wimbledon glory with a straight-sets victory in the semi-final.The Italian will defend his title against Alexander Zverev in Sunday’s final after a clinical 6-4 6-4 6-4 victory on Centre Court.Djokovic has reached the semi-finals or better in six of his past seven grand slams, a remarkable feat for a man who turns 40 next year.Novak Djokovic feels the heat against Jannik Sinner (Mike Egerton/PA) (PA Wire)But he cuts an increasingly listless figure at the sharp end of the tournaments, with the rigours of a fortnight of best-of-five-sets tennis taking its toll, not least that late-night, five-hour slog against Felix Auger-Aliassime in the quarter-final.That seemed to be the story here again. Sinner has not exactly been convincing