Serena Williams is poised to break Steffi Graf's 25-year-old record for consecutive weeks at world No. 1 but Angelique Kerber and Garbine Muguruza are relishing the opportunity to dethrone the queen of the sport. American 34-year-old Williams's latest spell on top of the pile started in February 2013. That's a stretch of 184 weeks which will become 186 during the the US Open fortnight and match Graf's mark set between 1987 and 1991. Kerber, a German compatriot of Graf, had her chance to snatch top spot last week by winning the Cincinnati title but faltered in the final, a slip-up which kept her at No. 2 heading into New York. "I love the question (of the number one ranking). I love it," said the 28-year-old Kerber, who defeated Williams in the Australian Open final in January for her maiden Grand Slam title. "Let's see what happens in the next two weeks." Kerber is right to be cautious having suffered in the past for allowing herself to get tied up in knots by predictions and permutations. Last year at the WTA Championships in Singapore, she needed to take just one set off Lucie Safarova to make the semifinals of the lucrative season-ender. Instead, she got so distracted by the "ifs", "whats" and "maybes" that she was defeated in straight sets and was eliminated. "I will not put too much pressure on this. If the day will come when I reach No. 1, that would be amazing," said the German. Muguruza, the world No. 3, has an outside chance of taking the top spot. But the 22-year-old Spaniard, who made her Grand Slam breakthrough with this year's French Open title by defeating Williams in the final, has time on her side. She is 12 years younger than Williams. When the American first made number one back in 2002, Muguruza was just eight. "I feel the discussion (over the world number one ranking) is much louder," said the Venezuelan-born player. "There are a couple of players that if they do really well and whatever the situations are, they can reach No. 1. So that creates a little bit of juicy comment." The discussion is louder also because of the caliber of the players involved — both Kerber and Muguruza are Slam winners. Over the last decade, however, there were a series of women who reached the No. 1 ranking without winning a major either at the time or since. Jelena Jankovic (18 weeks in total in 2008 and 2009), Dinara Safina (26 weeks in two 2009 spells) and Caroline Wozniacki (two periods stretching over 2010/11 and 2011/12 totalled 67 weeks). All three women made the finals at majors, went to No. 1 but never cracked a Grand Slam title. Jankovic was runner-up at the 2008 US Open, Safina made the finals of the 2008 Australian Open and 2008 and 2009 French Opens. Wozniacki was twice a finalist in New York — in 2009 and 2014. Six defeats in total — Williams was responsible for three of them.Murray poised to pounce Murray poised to pounce Andy Murray admits he's playing his best ever tennis as he looks to capitalize on the growing frailties of his rivals and capture a second US Open title. Ahead of Monday's start to the season's final Grand Slam, the 29-year-old is the sport's man of the moment. Since losing the French Open final to Novak Djokovic in June, Murray has won Queen's Club, a second Wimbledon title and successfully defended his Olympic crown in Rio. His career-best 22-match win streak came to a halt at the hands of Marin Cilic in the Cincinnati final last weekend when he simply ran out of gas. But that hasn't dented his confidence that he can claim a second US Open, four years after his breakthrough in New York saw him become the first British man in 76 years to win a Grand Slam title. At 29, three-time major winner Murray admits he is taking positives from being in the twilight of his career. Murray has played in all of the first three finals of the majors in 2016, losing to world No. 1 Djokovic in Melbourne and Paris before defeating Milos Raonic in straight sets in the Wimbledon final. The only worry for Murray is his relatively mediocre recent record in New York — runs to the quarterfinals in 2013 and 2014 were followed by a fourth-round exit to Kevin Anderson 12 months ago. Murray starts his campaign against fiery Lukas Rosol. The last time they met in Munich in 2015, the Scot described the Czech as the most-hated man in the sport. Murray's consistency on the tour in recent weeks is in stark contrast to the rollercoaster fortunes of Djokovic, the defending champion in New York. After he won a maiden French Open to complete the career Grand Slam, all talk was of the Serb going on to defend his Wimbledon and US Open titles and clinch a calendar Grand Slam. — Agencies