Having started his career at Manchester United, he went on to play 161 times in the Championship for Rovers.

Rothwell is Saints' second new signing after Irish teenager Joe O'Brien-Whitmarsh joined from Cork City.

"Hopefully I can come in and show my experience of this league and help them get over the line," Rothwell told the club website.

"I can't wait to finally get going and put my boots on, and hopefully we can get the club back to where it belongs."

Southampton are third in the Championship, just three points behind Ipswich in second place.

Director of football Jason Wilcox added: "Joe is a quality addition who gives us further strength and depth in the squad, which will be particularly important as the season goes on.

"We're very pleased to be able to bring in a player of his experience and ability."