MORTON have today completed the signing of former Dundee United and St Johnstone midfielder David Robertson.

The 27-year-old was available as a free agent after his contract with Saints expired on 31 December and becomes manager Kenny Shiels' third new recruit following the recent acquisitions of Darren Cole and Barrie McKay.

Robertson, son of Ton cult hero Dougie Robertson, has signed until the end of the season and goes straight into the squad for Saturday's crucial Championship clash at Dumbarton.

The Scotland Under-21 cap started his career with Dundee United and made over 120 top-flight appearances at Tannadice before joining St Johnstone in the summer of 2011.

In his two-and-a-half seasons with the Perth outfit, Bangour-born Robertson struggled with injuries and was subsequently released when his short-term contract expired at the end of last year.

However, Shiels has been impressed by the midfielder, both in training and a bounce game against St Mirren, and swooped to secure his signature as he attempts to put his own stamp on the Ton squad.