Between Andrei Olhovskiy and Jelena Janković, who became a pro earlier?
Jelena Janković Jelena Janković (Serbian Cyrillic: Јелена Јанковић, ] , born 28 February 1985) is a Serbian professional tennis player. Janković is a former World No. 1 in singles, a ranking achieved preceding her finals appearance at the 2008 US Open. Janković's career highlights include winning the 2007 Wimbledon Mixed Doubles title with Jamie Murray, the 2010 Indian Wells Masters, the Internazionali BNL d'Italia twice, in 2007 and 2008, and the aforementioned appearance in the finals of the 2008 US Open. She is coached by her brother Marko.
Petra Kvitová Petra Kvitová (] ; born 8 March 1990) is a Czech professional tennis player. Known for her powerful left-handed groundstrokes and variety, Kvitová turned professional in 2006 and has won 20 career singles titles, including two Grand Slam titles at Wimbledon. She is also an Olympic medalist, capturing the bronze medal at the 2016 Rio Olympics. She reached her career-high ranking of world no. 2 on 31 October 2011 and as of 18 September 2017, is ranked world no. 14 by the Women's Tennis Association (WTA). As such, Kvitová is the current second highest-ranked Czech and the second highest-ranked left-handed player in the WTA behind Karolína Plíšková and Germany's Angelique Kerber, respectively.