John Isner is into the semifinals of the Stockholm Open after defeating compatriot Tennys Sandgren in Sweden.
In the all-American contest, No. 1 seed Isner came out on top in a game of tiebreakers, 7-6 (8), 6-7 (5), 7-6 (2), and will now face Latvian qualifier Ernests Gulbis on Saturday.
Gulbis was too strong for No. 4 seed Jack Sock after the American took the first set; Gulbis eventually won 4-6, 6-3, 6-4 in their quarterfinal.
In the other half of the draw the No. 2 and No. 3 seeds will battle it out in the semifinals after Fabio Fognini and Stefanos Tsitsipas both came through their quarterfinal matches.
The fiery Italian Fognini won the first set against South Korea’s Hyeon Chung before he had to retire with the score 7-5, 2-1.
Meanwhile Tsitsipas saw off the challenge of German Philipp Kohlschreiber, eventually coming through in a second set tiebreak to win 6-3, 7-6 (4).