Complex sentence: He was promoted to the first team in the beginning of the 2012--13 season and debuted with the first team on 9 September 2012 against F.C. Paços de Ferreira.
Split into simpler sentences: He was promoted to the first team in the beginning of the 2012--13 season. He debuted with the first team on 9 September 2012 against F.C. Paços de Ferreira.