The midfielder joins the Bloomfield Road side on a free transfer from Dundee United on a two-year deal while Craig Sutherland suffers a knee injury during training
The 27-year-old had undergone a medical on Wednesday at Bloomfield Road and has penned a two-year deal.
The midfielder has spent the past four seasons with the SPL outfit and has the option to extend his new contract for a further year.
The Scotland international is the fourth signing this summer for manager Ian Holloway as he seeks to gain promotion to the Premier League.
The Tangerines boss will be without striker Craig Sutherland for the foreseeable future, however, after the 23-year-old sustained a knee injury during training.
A statement on the club's official website said: "He is now booked in to see a specialist and is likely to have surgery within the next seven days."