Security staff were called to the X Factor house after Black Country finalist Wagner Carrilho was accused of trying to damage rivals' vocal chords - by spraying deodorant.
Fellow over-28s contestant John Adeleye "flipped" when Wagner went around the house spraying deodorant, insisting the fumes were ruining his vocal chords, according to insiders at the house in London.
The row escalated over breakfast, as the eccentric Wagner retorted that John, aged 30, was acting like a "diva" and telling him: "Back off and act like a man," according to reports.
Security staff pulled the two men apart, but sources claim there is "some serious bad blood" among contestants. TV show bosses are getting worried that having the 14 remaining acts sharing one small house will lead to more rows.
Rumours are already rife of tensions in the girls' category, with bickering between Cher Lloyd, Katie Waissel, Rebecca Ferguson and Wolverhampton University student Treyc Cohen.
Treyc revealed earlier this week that controversial finalists Cher and Katie, both of whom failed to complete their audition at the judge's house stage, gave her a "frosty" reception. An
ITV spokesman said: "This year's house is bigger than ever but the fact is, lots of people who may have very little in common are in each other's pockets.
"The row between Wagner and John is typical. Two more different people you couldn't hope to meet."
A poster campaign has been launched in support of quirky former PE teacher Wagner, aged 54, of Blewitt Street, Pensnett, by friends and neighbours. He was sent home from the competition at the judges' house stage, but was re-introduced at Saturday's live show as Louis Walsh's "wild card" in the over-28s category.
The Express & Star yesterday revealed pictures of Wagner dressed in swimming trunks and holding a lion's tail.
The lion, given to the opera singer as a gift at just eight weeks old, used to curl up at night with his best friend, a Samoyed dog.
Wagner used to own The Martial Arts and Dance Gym in Elbow Street, Cradley Heath, which he closed down on becoming a PE teacher at Leasowes Community College, between August 2006 and September 2007.
Throughout that time, he was working for window, door and conservatory-fitting firm Conservatories Xpress at Netherton.