Australian Open 2013: Heather Watson targets top 30 after win

British tennis number one Heather Watson says she wants to be in "at least" the world top 30 this year, after going through to the second round of the Australian Open.

Watson, ranked 50th, came back from a set and a break down to beat Romania's Alexandra Cadantu 2-6 6-3 6-2 in Melbourne.

The 20-year-old from Guernsey said she lacked energy in her first-round match, during which she had to take a medical time-out for cramp.