Vale in June 2013. Upon securing him to a two-year contract, manager Micky Adams noted that Robertson had experience of League One football and had made a good impression on him during his time at Torquay. He opened the 2013–14 season in a centre-back partnership with Carl Dickinson. On 1 April he was sent off during a 2–1 win over Crawley Town after the referee mistakenly thought he had made a tackle from behind, when in fact the culprit was club captain Doug Loft. He ended the campaign with 44 appearances to his name, but said that he was not taking his future at the club for granted despite being one of only a few players contracted until 2015. At the start of the 2014–15 season he fell down the first team pecking order behind Richard Duffy, Ryan McGivern, Stéphane Zubar and Remie Streete, and was told by new manager Rob Page that he must go out on loan in order to find first team football. He said the club told him to leave for financial reasons and that "He [Page] explained to me that I was part of his plans, as long as he is here. Then a week later, he started signing centre-halves and loan players. I didn't really know what was going on." He was released in May 2015. Ross County Robertson signed for Scottish Premiership club Ross County in June 2015. In making the move he turned down better financial offers from lower league English clubs. He broke his hand in pre-season and started the 2015–16 season on the bench. He was an unused substitute in the Scottish League Cup Final at Hampden Park, as the "Staggies" won the Scottish League Cup for the first time in their history. His contract was terminated by mutual consent in August 2016. AFC Wimbledon Robertson returned to League One in September 2016 after signing with AFC Wimbledon. He joined the club so as to move his pregnant wife closer to family. An injury to Darius Charles allowed him to form a centre-back partnership with Paul Robinson. He scored his first goal for the "Dons" in a 4–0 win over former club Port Vale at the Kingsmeadow on 17 December. However he was limited to just 19 appearances throughout the 2016–17 campaign, and manager Neal Ardley decided to release Robertson in May 2017 so as to allow a path to