Last weekend, Lyon blew a two-goal lead in injury time to draw 2-2 at Nice, leaving them eight points behind leaders Lille.
A few days later, fourth-placed Lyon, who host lowly RC Lens on Sunday, suffered a further dent to their fragile composure.
Although Grenier missed Wednesday's training because of bruises, president Jean-Michel Aulas's special advisor Bernard Lacombe played down the incident.
"To me, it's nothing," he said on the club's website. "It was (Cris's) way to show that he did not like what happened in Nice."
TV cameras showed Lloris screaming 'We badly screwed up, I've had it up to here with this, holy shit!' in the dressing room after the Nice game.
"He expressed huge frustration. He is a lad who usually keeps things for himself and he just needed to let it go out," coach Claude Puel told reporters.
Lille are expected to welcome back France defender Adil Rami, who suffered a neck injury during Les Bleus's 0-0 draw with Croatia at the Stade de France last month.
Second-placed Olympique Marseille, who are four points behind Lille, host Toulouse on Saturday amid a row between president Jean-Claude Dassier and coach Didier Deschamps over theb's clu recruiting policy for the 2011/12 season.
"I heard the president had the same goal as me, winning the Champions League," Deschamps said last Sunday.
"But (he also said that) the club's policy would be to sign young, talented free agents. It seems to me that both things are hardly compatible."
"We are not going to spend millions and millions," Dassier replied in French media.
