From 2006, Krkoška regularly played tournaments with the professionals, mainly tournaments on the third-class ITF Future Tour . While he often failed in the first two rounds in singles, he won his first three titles in doubles in 2007, which ended the year in the top 500 of the world rankings . In the following year he improved his position by further double titles, in the individual he increasingly managed to get into the quarter-finals, which resulted in a 758th place, his career best.
In 2009 Krkoška also competed in tournaments of the higher endowed ATP Challenger Tour , where he was able to achieve smaller successes in doubles. After he failed in the semi-finals in Qarshi , he reached the final in Saint-Rémy-de-Provence . There he beat the Belgian duo Ruben Bemelmans and Niels Desein at the side of Lukáš Lacko in three sets and celebrated his only challenger title. With further finals in Tashkent and Bergamo , he continued to improve in the world rankings, so that in March 2010 he achieved his best placement with 167th place. He played his last game in September 2010 at the Challenger in Trnava .