Jimmy Nicholl followed Calderwood when he took over as manager at Aberdeen, again serving as his assistant until the two parted company with the club in May 2009. He resumed his partnership with Calderwood at Kilmarnock in 2010. Nicholl was appointed manager of Cowdenbeath in June 2010, but he left Cowdenbeath at the end of the 2010–11 season after they were relegated from the First Division. Nicholl was then appointed assistant manager of Kilmarnock for a second time, by Kenny Shiels on 15 June 2011. Kilmarnock won the 2011–12 Scottish League Cup under Shiels and Nicholl, but Shiels was sacked by Kilmarnock
Dean Shiels cost-cutting that is due to take place at the club; manager Ally McCoist refuted this. On 8 February 2014, Shiels scored a hat-trick in the Scottish Cup, as Rangers won 4–0 against Dunfermline Athletic. On 10 June 2016, Shiels left Rangers after his contract came to an end. He had made 43 appearances for Rangers in his final season with the club, as they won promotion to the Scottish Premiership. On 25 August 2016, Shiels signed for Dundalk in the League of Ireland Premier Division citing the "lure of European football" as one of the things that attracted him to