We have caught them peeing in the swimming pool.
Speaking in Manchester at the Soccerex conference, Tebas suggested that PSG had mocked UEFA's financial fair play (FFP) regulations by completing that deal and the loan of Kylian Mbappe from Monaco, which is set to become a €180m deal next summer.
The Costa Rican-born administrator expanded on this at Soccerex, saying clubs backed by national gas and oil revenues were inflating costs for all clubs and destroying the industry.
Several Spanish clubs, including Real and Barca, were punished a year ago for breaching rules on state aid but Tebas dismissed any comparison between those cases and the FFP breaches he was accusing City and PSG of.
Tebas remains adamant that Uefa need to investigate PSG for Financial Fair Play (FFP) reasons, and admits he believes the French giants could in the future use their considerable wealth to snap up even bigger names. "PSG and Manchester City and in the past from Chelsea".
UEFA, who are investigating PSG's spending, have said they are not looking into City. "That is impossible. That is financial doping".
"This is when the football clubs have competitive advantage not coming from club itself".
"Mr Tebas's statements are ill-informed and in parts pure fiction", said City Football Group (CFG), which owns the Manchester club, in a statement to local media.
PSG chief Al-Khelaifi: Those "thinking about FFP I tell them ... go have a coffee and don't worry about us, we are in good hands".
"As you would expect, Manchester City Football Club and the City Football Group are seeking appropriate legal counsel and will act accordingly on that advice". He also accused UEFA of being too soft on those Arab-owned clubs after they were both sanctioned for breach of financial regulations in 2014. Now Neymar has gone on the diving board and peed from the diving board. "We can not let them get away with this", he said at the Soccerex conference in Manchester.
"We need to change the system because the damage has already been done when Uefa hands out punishments", said Tebas.
As a way of attempting to improve his credibility, La Liga boss Tebas cited his previous criticism of Sepp Blatter and Michel Platini, noting: 'Where are they now? They have agreed on sponsorships that are above market price.