The equality was maintained until the tenth point, when the German, again with his left hand, broke the serve of the Spanish, and later took the tie-break by 7-4.
Del Potro continued his run at the Masters event as he overcame a 1-4 deficit to defeat No. 22 seed Filip Krajinovic of Serbia 6-4, 6-2 for his 14th consecutive victory.
It was a match full of shifts in momentum, with seven service breaks in the first four games, although none of them ultimately worked to Sakkari's advantage.