With Federica Testa, he won four ISU Challenger Series medals and bronze at the 2015 Winter Universiade.

[8] In October 2011, Slovak news media reported that Csölley had teamed up with Italy's Federica Testa to compete for Slovakia.

[9][10] Coached by Roberto Pelizzola in Milan, Testa/Csölley made their international debut at the Bavarian Open in February 2012 and then competed at the World Championships in March in Nice, France.

[12] They began their season with a bronze medal at the 2014 Ondrej Nepela Trophy, an ISU Challenger Series (CS) event held in early October.

Later that month, making their Grand Prix debut, they placed fourth in the short dance and seventh overall at the 2014 Skate America.

Testa/Csölley received invitations to the 2016 Skate Canada International and 2016 Trophée de France but withdrew from both Grand Prix events on 7 July 2016[14][15] due to Testa's decision to retire from competition.

[18] Myslivečková/Csölley won gold at the Volvo Open Cup in November 2016 and placed 16th at the 2017 European Championships in Ostrava, Czech Republic.

In mid-March 2017, they decided to withdraw from the World Championships in Helsinki due to Myslivečková's shoulder injury, requiring an operation.

[20] In late September, the duo competed at the 2017 CS Nebelhorn Trophy, the final qualifying opportunity for the 2018 Winter Olympics.