Poland’s Hubert Hurkacz produced a stunning performance to down world number one Daniil Medvedev 6-1, 6-4 and claim the Halle ATP grass title on Sunday. Last year’s Wimbledon semi-finalist warmed up perfectly for this year’s tournament beginning on June 27 by racing into a 5-0 lead against the Russian and never looking back. He broke again in the first game of the second set with Medvedev struggling to deal with his excellent returns in Germany. “I am very happy with the win,” the first Polish winner at Halle said courtside. “He is the best player in the world. So it is very tricky.” A booming…