Emmanuel Dennis and Ismaila Sarr are among four players that have not joined Watford for their pre-season training camp in Austria.
The Hornets flew out to Walchsee on Tuesday morning with Dennis and Sarr, plus Adam Masina and former Magpies loanee Danny Rose all staying behind in Hertfordshire, as per The Athletic.
Newcastle United have been linked with both Dennis and Sarr during the summer months as the pair eye a move away from Vicarage Road.
Senegalese forward Sarr has been a player of interest to the Magpies since January but have not yet made a move with other targets currently under consideration.
Sarr joined the Hornets from French club Rennes in a £27million deal in the summer of 2019 and has made 92 appearances and scored 24 goals in total.
The 24-year-old was restricted to just 22 Premier League outings last season, where Watford were relegated, due to injury.
Dennis, meanwhile, has been tentatively linked with United.
Everton, West Ham, Southampton and Fulham all hold genuine interest in the £20m-rated striker, whereas Newcastle’s interest hasn’t been as concrete.
The Nigerian international finished as the club’s top scorer in the top-flight last term with 10 goals.
Both players will continue their preparations for the new season at Watford’s training ground until an expected opportunity to leave arises.
The Hornets conclude their visit to Austria with a pre-season friendly against Greek side Panathinaikos on Sunday afternoon.
Eddie Howe’s side also jet out to Austria next week for a week-long training camp where they take on German sides 1860 Munich and Mainz 05.