Steven Hammell has returned to Motherwell from Southend United as the Scottish Premier League club also took Norwich City's Simon Lappin on loan.
Lappin has fallen out of favour at Carrow Road
Southend had rejected an initial offer for 25-year-old Hammell but accepted a bid of £110,000 on Thursday.
Hammell, who moved to Southend as they entered the Championship in 2006, has signed a two-and-a-half year contract.
Meanwhile, former St Mirren midfielder Lappin, who turned 25 this week, has signed until the end of the season.
Lappin joined Norwich from the Buddies in January 2006.
He made 18 appearances this season but has not played since November after falling out of favour following Glenn Roeder's appointment as manager.
Hammell has been a regular starter for Southend after their relegation from League One.