The 29-year-old has never been in the long-term plans of Felix Magath and spent the second half of last season on loan at PSV Eindhoven.
After playing a starring role for his country at the World Cup finals, Ruiz was linked with the likes of Ajax and Dynamo Kiev.
But now Bundesliga outfit Werder have emerged as the favourites to land the former FC Twente star.
Reports in Germany claim that Ruiz has already agreed personal terms with the Bremen outfit and now all that is lacking is an agreement between the two clubs, with Werder looking for a permament deal.
Werder general manager Thomas Eichin confirmed to BILD that they are closing on a deal and said: "Maybe our time (to sign Bryan Ruiz) has come!"