Viola mainly plays on the ATP Challenger Tour and the ITF Future Tour . So far, he has won nine singles and seven doubles on the Future Tour. There are also three successes in singles and four in doubles in Challenger tournaments. He made his debut at a Grand Slam tournament in January 2012 when he qualified for the main draw of the Australian Open in three qualifying rounds . There, in the first round, the Colombian Santiago Giraldo clearly lost 4: 6, 2: 6 and 1: 6. On the ATP World Tour he qualified for the tournament in Zagreb , where he lost to Łukasz Kubot , and for the tournament in Gstaad , where Jan Hernych defeated him in the first round.