Martin Slanar, who was born in Prague, moved to Austria when he was seven. There he also started tennis and was trained by his father František. On the professional tour, Slanar mainly played tournaments of the lower class ITF Future and ATP Challenger Tour . The Future Tour won a total of ten doubles titles. He won a total of seven titles on the Challenger Tour, all of them in doubles.
He made his Grand Slam debut in 2008 at the Australian Open . Completely surprisingly, he survived the qualification and made it into the main field of the individual competition. There he played against Dudi Sela , who was placed over 200 places better and was clearly defeated in three sets. In the same year he also made his debut on the ATP World Tour by qualifying for the main draw in Tokyo . He managed a win against Donald Young in the first round , but had to admit defeat to Richard Gasquet in the second round . In 2011 he finally made it into a main field in doubles. In Johannesburg he competed alongside Philipp Oswald , but was clearly defeated by local heroes Rik De Voest and Izak van der Merwe in the first round . Slanar made it into the top 200 of the world rankings with a 198th place . He was more successful in doubles and was able to place himself in the top 100 with a 94th place at the end of 2010. After the tournament in Dortmund in 2011 , Slanar ended his career due to numerous injuries and illnesses.
In 2017 he played another tournament in Panama City at the side of Iván Rebolledo . They lost in the first round to Ariel Behar and Fabiano de Paula . Otherwise, Slanar has been a youth coach since the end of his career and also looks after players on the tour.