After reaching a milestone 50 successive international match victories in last month's Seoul Open in South Korea, Malaysian Nicol David has extended her lead at the top of the new May Women's World Squash Rankings, published today (Wednesday) by the Women's International Squash Players' Association (WISPA).

April was an eventful month for the 23-year-old from Penang who began her unbeaten run in July last year.  David won both the Kuwait Open and Qatar Classic, then reached her 13th successive WISPA World Tour final - and her fifth meeting in a row with Australia's Natalie Grinham - on the all-glass court at Seoul Plaza.

Grinham prevailed to record the first win over her great rival for over a year - and strengthen her status as the world number two.

Natalie's older sister Rachael Grinham holds onto her position at three, ahead of fourth-placed Tania Bailey and her English compatriot Vicky Botwright at No5.

Ireland's Madeline Perry rises two places to No8 in the May list - strengthened by her success in retaining the Irish Open title for the third year last month in Dublin.

England's Jenny Duncalf also has cause for celebration - moving back into the top ten at 10 after a quarter-final berth in the Kuwait Open and a semi-final finish in Seoul.

Outside the top 20, Mexico's Samantha Teran jumps to a career-high No22 after winning the Southport Open in the USA, then securing the Toronto Open title last month in Canada.

          1        [1]      Nicol David     MAS
          2        [2]      Natalie Grinham        AUS
          3        [3]      Rachael Grinham       AUS
          4        [4]      Tania Bailey   ENG
          5        [5]      Vicky Botwright        ENG
          6        [6]      Natalie Grainger        USA
          7        [7]      Omneya Abdel Kawy  EGY
          8        [10]    Madeline Perry          IRL
          9        [8]      Vanessa Atkinson      NED
          10      [11]    Jenny Duncalf ENG
          11      [9]      Alison Waters ENG
          12      [12]    Laura-Jane Lengthorn          ENG
          13      [13]    Shelley Kitchen         NZL
          14      [14]    Engy Kheirallah         EGY
          15      [15]    Rebecca Chiu HKG
          16      [16]    Kasey Brown  AUS
          17      [17]    Isabelle Stoehr         FRA
          18      [18]    Annelize Naude         NED
          19      [19]    Sharon Wee   MAS
          20      [20]    Dominique Lloyd-Walter       ENG

For the complete WISPA ranking list, see www.wispa.net