He began the 2010 season in the CEV Buckler 125cc championship, competing with the Monlau Competición team, along with Álex Rins and Niklas Ajo. Márquez did not participate in the opening round at Circuit de Barcelona-Catalunya, as he was not old enough to do so – he did not turn fourteen until five days after the event. He finished eleventh in his first start at Albacete, having qualified tenth. He retired at Jerez due to clutch problems. He added finishes of seventh and sixth at Motorland Aragón and Albacete, before retiring from the final two races at Valencia and Jerez. He finished eleventh in the final riders' championship standings.