He will join Geoff Appleford and fellow countryman David Quinlan as Saints’ new centres to complement the young Academy-produced talent of Andy Vilk and Neil Starling. Starling, however, will miss the start of the season to continue his rehabilitation for an operation he had on a knee injury. He is likely to return to action in February.

Head coach Budge Pountney said: “Seamus needed a change from Ulster and will relish the chance to prove himself here at Northampton. I think the environment here will enable Seamus to develop his game and give him ample opportunities to impress.”