The Athletic on Thursday claimed the pair had to be separated last week when Luiz took exception to a challenge from Ceballos and punched him in the face, drawing blood.
Ceballos reportedly went to retaliate but they were swiftly separated by team-mates and staff and sent home for three days, returning to London Colney on Tuesday.
It is claimed the pair apologised to the rest of the squad and settled their differences upon their return.
But Ceballos has firmly denied the allegations, simply branding them “FAKE” in a blunt rebuttal on Twitter.
Arsenal are back in action on Sunday as they take the trip up north to face Leeds United, both clubs looks to make amends for humbling defeats last time out.
The Gunners were wretched against Aston Villa before the international break, going down 3-0 at home, after Crystal Palace had stuck for past Marcelo Bielsa’s side.
This weekend get a £10 free bet with Betfair, when you bet £10 on a Same Game Multi on the Premier League.
Terms: Min £10 Same Game Multi bet on any EPL match this Fri – Sun. Free bet valid for 72 hours, awarded at bet settlement. Excludes cashed out bets. T&Cs apply.