Meyer was a free agent following the expiration of his contract with Bundesliga side Schalke, where Meyer was frozen out by the club after clashing with senior officials. After arriving at Crystal Palace last week, he may not be fit enough to take part in their clash with Fulham on Saturday.
The claim comes from the Evening Standard, who state that Meyer is still in the early stages of his pre-season training. His first training session with his new club took place last Friday, but Meyer was not involved in their pre-season clash with Toulouse as he strives to regain his fitness.
Meyer's last appearance for Schalke came towards the start of April but, after criticising sporting director Christian Heidel, he was not involved in training sessions and did not train with a club following his release from Schalke. As a result, Meyer had not trained with a side for around four months.
The Eagles are monitoring his progress, but it appears as though he will not be ready for their clash with Fulham on Saturday.
Meanwhile, fellow signing Cheikhou Kouyate is also facing a race against time to be ready for the match. The 28-year-old captained Senegal at the World Cup this summer and took an extended break following their elimination from the tournament.
He did feature in the friendly match with Toulouse, but was only afforded 17 minutes, suggesting he is not physically ready to play a significant part in the Premier League encounter.
Vicente Guaita looks set to be the only new signing to be involved against Fulham, as the Spainard will take over from Wayne Hennessey in goal.