New York, Sep 1 : Russian Daniil Medvedev secured his 250th hard-court victory late at night against Australian Christopher O'Connell on Day 4 in the US Open. In the third set tie-break, Medvedev outclassed the Australian with his depth of the court and ability of ground coverage. With this win, he went straight into the third round clocking back at 2021 when he won the US Open final defeating Serbian Novak Djokovic straightaway in three sets. Another Russian, Andrey Rublev, the eighth seed, also impressed, showcasing his resiliency and consistency in defeating Gael Monfils. Both players' tenacity was on display during their protracted rallies, but Rublev's higher level of consistency allowed him to move to the third round. Alexander Zverev, who had previously reached the US Open final, also kept up his quest for a major championship. The German increased his prospects of making it to the ATP Finals after defeating countryman German Daniel Altmaier in a gripping match. Former champion Andy Murray and American powerhouse John Isner saw their journey come to an end on a day of intense action and compelling matchups. Under the hot sun at Arthur Ashe Stadium, Murray had to contend with Grigor Dimitrov. Meanwhile, Isner, who is renowned for his extended bouts, made a spirited attempt but was ultimately unsuccessful in the singles competition. The American became well-known for playing Nicolas Mahut in a historic 11-hour, 5-minute Wimbledon match in 2010. However, Isner declared his retirement plans but was unsuccessful in claiming a victory to round off his career. Isner didn't get the send-off he had anticipated when fellow countryman Michael Mmoh came back from being down two sets to overcome him. Earlier in the tournament defending champion Carlos Alcaraz continued his dominance and propelled to third round after a dominant performance against Australian Lloyd Harris. Alcaraz will face British player Daniel Evans in the following round as he moves on to face yet another tough foe. Some outstanding performances in the women's competition raised the excitement of Day 4 much more. With a score of 6-3, 6-1, third-seeded Jessica Pegula easily defeated Patricia Maria Tig in her match. By coming back from a set down to overcome American Sofia Kenin, Russian Daria Kasatkina demonstrated her tenacity. Kasatkina persevered and made tactical changes to clinch victory and move on to the third round of the match. Earlier last year's runner-up Ons Jabeur overcame Czech Teenager Linda Noskova and went into the third round. Aryna Sabalenka, the 2023 Australian Open winner, advanced to Round 3 after defeating Jodie Anna Burrage in straight sets. /IANS