Jeroni is one of the historic riders with the longest career in the X-Trial World Championship. He debuted in the competition in 2005, already achieving his first points with a sixth position in the X-Trial Sheffield. His first world championship podium, out of a total of 28, was achieved in the X-Trial Barcelona by taking third place and, that same year, he achieved his only victory in the championship in the 2005 X-Trial Buenos Aires (Argentina).