Portsmouth manager Paul Cook has signed Benin international Romuald Boco for the sixth time.
The 30-year-old midfielder played under Cook at Sligo Rovers three times between 2008 and 2012, as well as at Accrington and Chesterfield.
The duo also played together at Stanley in 2005-2006.
Boco has signed on a deal until the end of the season and has been sent straight out on loan to National League South side Havant & Waterlooville.
The 48-time capped international made 19 appearances for Chesterfield last season before leaving in January to join Indian side Bharat FC.