NEW YORK-Serena Williams was sent spinning out of the Western and Southern Open by Maria Sakkari on Tuesday after the Greek rallied from a set down to beat the 23-times Grand Slam champion 5-7 7-6(5) 6-1 and reach the quarter-finals. 
Williams, 38, raced to a 5-2 in the opening set before Sakkari drew level but the American raised her game again to take the early advantage in the rain-delayed contest. Williams trailed 3-1 in the second set before reeling off four games in a row and was serving for the match when things began to fall apart. World number 21 Sakkari dragged the set to a tie-breaker before levelling the contest at 1-1, then surged to a 5-0 lead in the decider and completed the upset win on her eighth match point with a powerful forehand. 
Sakkari said she did not play well but was delighted with the victory over the third seed. “I knew it was going to be an ugly match from my side but I’m extremely happy with the result,” Sakkari said. “She’s a role model for me and many others. What she has achieved in our sport is unique and I don’t know if anyone else is going to do it again.” Sakkari next faces Briton Johanna Konta, who got past Vera Zvonareva 6-4 6-2. 
Earlier, Naomi Osaka put on a solid serving performance to beat Dayana Yastremska 6-3 6-1 and advance to the quarter-finals where she will face Anett Kontaveit, who beat Marie Bouzkova 6-3 6-3. Osaka fired eight aces to zero for Yastremska and needed just over an hour to dispatch the 20-year-old Ukrainian. Former world number one Victoria Azarenka improved her record against Alize Cornet to 7-0 with a 6-4 7-5 win to advance to the quarter-finals, where the Belarusian will meet Ons Jabeur, who beat Christina McHale 6-3 6-0. 
DJOKOVIC ROLLS ON, MURRAY ELIMINATED
Top seed Novak Djokovic made quick work of Tennys Sandgren at the Western and Southern Open on Tuesday, never dropping serve en route to a 6-2 6-4 win over the American, while big-serving Milos Raonic enjoyed a straight sets win over Andy Murray. Djokovic broke Sandgren three times to reach the quarter-finals and extended his win-loss record to 20-0 this year. Next up for Djokovic is German Jan-Lennard Struff, who outlasted David Goffin 6-4 3-6 6-4 earlier on Tuesday. 
Murray had an impressive win over fifth seed Alexander Zverev on Monday but never found his rhythm against Raonic. The Canadian dominated on serve, firing 10 aces and winning almost 90% of his first-serve points, to advance to the quarter-finals 6-2 6-2 in a rain-interrupted match that marked his first win over the Briton since 2014 at Indian Wells. 
Defending champion Daniil Medvedev looked sharp in his stress-free 6-3 6-3 dismantling of qualifier Aljaz Bedene to reach the quarter-finals. Stefanos Tsitsipas defeated John Isner 7-6(2) 7-6(4) and Reilly Opelka beat sixth seed Matteo Berrettini 6-3 7-6(4). Roberto Bautista Agut and Filip Krajinovic also advanced.