Matched up against one of the more experienced players in women’s tennis, 17-year-old Kayla Day of Santa Barbara made her professional debut at the Australian Open on Tuesday and lost to Germany’s Andrea Petkovic, 6-3, 6-2.
Petkovic, 30, has been on the pro tour for 11 years and was ranked as high as No. 9 in singles. She reached the quarterfinals of the Australian, French, and U.S. Opens in 2011.