In the summer of 2013, it was officially announced that he was loaned out to Groningen, in the Eredivisie. He made his debut against NEC Nijmegen in a 4-1 win. He scored his first league goal against Go Ahead Eagles, on 25 August, which was the second goal. The match ended in a 3-3 away draw, where he received a red card in the 68th minute for an elbow. Adorján scored his second goal, the team's third, in injury time during a 4-1 win against RKC Waalwijk.