His first game on the professional tour was in April 2011 at the Barcelona Open Banc Sabadell , when he failed in the first round to Benoît Paire . A month later he won his first Challenger tournament in Alessandria, Italy . In the same year his second Challenger victory followed in Como , where he defeated the German Andreas Beck in the final. Due to persistent back problems, he hardly played any games in the 2012 season and therefore only took part in twelve tournaments. In the 2013 season he also played increasingly on the ATP World Tour , where he was able to defeat fellow countryman Pablo Andújar in Casablanca and Robin Haase in the first round in Barcelona . At the tournament in Oeiras , Portugal , he again qualified for the main draw and advanced to the semi-finals, but ultimately failed the eventual tournament winner Stanislas Wawrinka in three sets. Nevertheless, 2013 was Carreño Busta's most successful season to date. Out of a total of 110 games, he won 92, more than any other player this season. He became only the fifth player to play more than 100 games in one season. He won a total of four tournaments on the Challenger Tour in 2013 and, thanks to his successes, moved up from 715th place at the start of the season to 64th place in the world rankings. He was therefore named Most Improved Player by the ATP .
At the Australian Open 2017 , Carreño Busta reached the third round. In Rio de Janeiro he reached the final, which he lost to Dominic Thiem 5-7 and 4-6. He won the tournament in doubles with his partner Pablo Cuevas . In the final they defeated Juan Sebastián Cabal and Robert Farah 6: 4, 5: 7 and [10: 8]. Carreño Busta recorded the third tournament victory in his career at the Millennium Estoril Open after beating Gilles Müller in the final . At the French Open he reached the quarterfinals for the first time after a five-set win over Milos Raonic , in which he had to give up against Rafael Nadal in the second set due to an abdominal muscle injury. Despite his injury-related non-participation in the tournament in Wimbledon, he then marked new career highs with rank 16 in both the singles and doubles world rankings.