By Ken Miller, Lawn Tennis Correspondent, Posted: Saturday, September 6, 2008 8:21am CST USA

NEW YORK--(lawntennismag.com) Two former world number ones Roger Federer of Switzerland and Serena Williams of the USA take to the US Open courts today as they attmept to regain the world's top rankings. Federer won the US Open title the last four years while Williams won in 1999 and 2002. The level of both players' game had dropped earlier this year before returning to highs again in New York. Roger Federer and Serena Williams

A win tonight for Serena Williams or Jelena Jankovic would return the winner to the WTA Tour's number one ranking Monday. Novak Djokovic (SRB)[3] v. Roger Federer (SUI)[2] Roger Federer leads Novak Djokovic head to head 6-2, but Djokovic won their last major meeting at the Australian Open in January 7-5, 6-3, 7-6(7-5). Federer was facing an illness at the start of the year and is playing better this week however. Federer has won 33 matches in a row at the US Open during the last 5 years claiming the title the last four years. Federer is the best player at the net and will use his net game for the edge. Prediction: Roger Federer Rafael Nadal (ESP)[1] v. Andy Murray (GBR)[6] Rafael Nadal won the French Open, Wimbledon and the Olympics before ascending to the number one ranking earlier this summer. Murray has improved his game as well and cites hardcourts and this tournament specifically as his favorite. But he is 0-5 versus Nadal losing last 7-6(7-2), 6-3 a few weeks ago in Canada on hardcourts. Murray has the explosive groundstrokes, speed and variety in his game to worry Nadal. But I think Nadal in the end will have the edge due to his experience and fitness. Prediction: Rafael Nadal Serena Williams (USA)[4] v. Jelena Jankovic (SRB)[2] A win tonight for Serena Williams or Jelena Jankovic would return the winner to the WTA Tour's number one ranking Monday. Jankovic reached the top spot earlier this summer without reaching any major final due to her very consistent play over the last 52 weeks. Her problem today could be consistency may not be enough if Serena Williams is on top of her power game. Jankovic is one of only a handful of players who don't trail Williams head to head. Williams is tied with Jankovic 3-3 and won their last meeting in the Miami final 6-1, 5-7, 6-3 in March. But Williams lost their last major meeting in Janaury at the Australian Open 6-3, 6-2 in the 4th round with a flat performance. Jankovic is a long rally queen and will attmept to draw Williams into extended baseline rallies and errors. Williams will need to attack and keep points short because Jankovic can be the more consistent player at times. If Williams can hit more winners than errors, she will be tough to beat. Prediction: Serena Williams