Marklund raced the 2014 FIA World Rallycross Championship for Marklund Motorsport in a Volkswagen Polo Supercar. He made 5 finals, including a career-best 2nd in Canada. He ended the season 6th in the points, having scored points in every event.
In 2015, Marklund raced at the FIA World Rallycross Championship with Mattias Ekström's team, EKS RX, driving an Audi S1 at races except Canada, where he drove a Volkswagen Polo. He endured a tough start to the season, rolling in the season opener in Portugal and launched off Daniel Holten in Sweden. He finished the season strongly, with a 6th in Turkey and a 4th in Italy. Also in 2015, Marklund also ran in the Audi Sport TT Cup, finishing 16th in the standings with 63 points and a best finish of 8th.
For the 2016 FIA World Rallycross Championship, Kristoffersson Motorsport and Marklund Motorsport combined their operations to participate under the brand Volkswagen RX Sweden. Driving a Volkswagen Polo Supercar, Marklund finished 13th in points, with best results of fourth at Belgium and Sweden.
He left the World Rallycross Championship in 2017, and returned to the European Rallycross Championship with Marklund Motorsport. He won the title with three wins in five races.
Racing record
Complete FIA European Rallycross Championship results