Watford are set to sign Spanish midfielder Mario Suarez from Fiorentina for a fee believed to be about £4m, reports BBC Three Counties Radio.
The 28-year-old has only made 13 appearances since joining the Italian side from Atletico Madrid last July.
He played 121 league games in five years at Atletico, scoring four goals.
Suarez, capped three times by Spain, also worked with Hornets manager Quique Sanchez Flores when he was Atletico boss between 2009 and 2011.
Meanwhile, Lithuania international goalkeeper Giedrius Arlauskis, 28, has completed a loan move to RCD Espanyol until the end of the season, having only made one appearance since joining the Hornets in the summer.