Watford have had a club-record bid of about £7m accepted by Genoa for Argentina winger Diego Perotti.
Capped twice by his country, the 26-year-old moved to Serie A last summer and scored four goals in 27 matches.
The Hornets' current record signing is Nathan Ellington, who cost £3.25m from West Brom in 2007.
Perotti was part of Sevilla's Europa League-winning team in 2014 before his move to Italy. He also won the Spanish Cup during his eight years at the La Liga club.
He made his Argentina debut against Spain in November 2009.
Watford, who finished runners-up in the Championship last season, appointed former Atletico Madrid manager Quique Sanchez Flores as their fifth boss in a year earlier this month.