Van Dijk initially struggled to break into Groningen's first team with club stuff believing he was "overtired" after extensive playing time with Willem II's academy and reserve sides.[1] He made his professional debut for the club on 1 May 2011, coming on as a 72nd-minute substitute for Petter Andersson during a 4–2 victory against ADO Den Haag.[11] On 29 May, and against the same opposition, he made his first start for Groningen and scored his first professional goals, netting twice in a 5–1 win in a UEFA Europa League play-off match.[10]