Cincinnati Masters on Friday. Top seed Medvedev fired 18 aces among 30 winners in a 7-6 (7/1), 6-3 defeat of Taylor Fritz in their Friday quarter-final. Tsitsipas, semifinalist at the last two editions, weathered a brief first-set rain interruption on the way to his 7-6 (7/5), 5-7, 6-3 defeat of John Isner, playing here for the 15th time at age 37 and the oldest quarterfinalist since 1969. The Greek fourth seed won the opening set in a tiebreaker but found himself level at a set each after Isner slammed down an overhead to break in the penultimate game and served to square the match a game later. In the third, Tsitsipas secured a break for 4-3 as Isner went wide; the seed sent over a service winner on his first match point to advance after more than two and a quarter hours despite 18 Isner aces.