In January 2008, Russia won at the age of 17 years the junior competition at the Australian Open. Throughout the tournament, they gave not a single sentence. In the final they defeated the local favorite Jessica Moore. On 7 July 2008 Rus took the lead in the Junior World Ranking.
In September 2008 she qualified for the International Women's Open in Guangzhou, China. In the first round she beat Yanina Wickmayer of Belgium there and reached after a victory over Gisela Dulko the quarter- final, which she lost to Frenchwoman Camille Pin.
2012 succeeded Rus her best result at a Grand Slam tournament when she beat the German Julia Goerges in three sets in the third round of the French Open and was able to move into the last sixteen. There, she defeated Kaia Kanepi of Estonia with 1:6, 6:4, 0:6.
In the German Bundesliga Arantxa Rus Tennis - 2006-2011 for the TC Blau-Weiss Bocholt.