Having featured regularly for Dundee's U20 side, including playing in a Challenge Cup tie against Cove Rangers,[2] Waddell was named among the substitutes for a handful of senior league games during the 2016–17 season, without making an appearance.
On 30 March 2017, Waddell, along with Dundee teammate Kyle Gourlay, signed on loan for Scottish League Two club Clyde until the end of the season.
[3] Waddell made his competitive debut for Dundee on 18 July 2017, against Raith Rovers in the Scottish League Cup, replacing Darren O'Dea after 82 minutes.
[6] Waddell moved on loan to Scottish Championship club Greenock Morton in July 2018.
[8] Waddell scored his first goal for the club with the opener as Morton defeated Peterhead in the Scottish Cup.