Second seed Tsitsipas knocked out by Khachanov, Alcaraz and Medvedev advance
Second seed Stefanos Tsitsipas was bundled out of the Miami Open in straight sets during Tuesday's fourth round by 2022 US Open semi-finalist Karen Khachanov.
The Russian 14th seed prevailed 7-6 (7-4) 6-4 over Tsitsipas in one hour and 34 minutes, powering 25 winners and making only nine unforced errors, compared to the Greek's 14.
Khachanov's triumph ended a winless 0-6 head-to-head record against Tsitsipas, while it also snapped his own 23-match losing streak against top-10 opponents.
The Russian, who also made this year's Australian Open semi-finals, has qualified for four of his six tour-level events this year.
Khachanov will take on 25th seed Francisco Cerundolo in the quarter-finals, with the Argentinian fighting back to get past Lorenzo Sonego 3-6 6-3 6-2 in just over two hours.
Defending champion and top seed Carlos Alcaraz had less trouble against Tommy Paul, cruising into the quarter-finals with a 6-4 6-4 victory.
Alcaraz won the winners' count 24-9, setting up a quarter-final clash with ninth seed Taylor Fritz, as the Spanish 19-year-old chases a rare Sunshine Double, having won last week's Indian Wells Open.
Fritz progressed after getting past seventh seed Holger Rune 6-3 6-4 in 86 minutes, sending down eight aces and 22 winners for the match.
Fourth seed Daniil Medvedev played late into the evening after a lengthy rain delay in Miami, but made light work of Quinten Halys 6-4 6-2, triumphing just past 1:30am local time.
Medvedev, who is into his third straight Miami quarter-final, will face American qualifier Christopher Eubanks in the last eight after he got past Frenchman Adrian Mannarino 7-6 (7-2) 7-6 (7-5) in another rain-delayed contest.
Italian 10th seed Jannik Sinner knocked off sixth seed Andrey Rublev 6-2 6-4, advancing to face Emil Ruusuvuori after he beat Botic van de Zandschulp 4-6 6-4 7-5.