Warnock, who took over as Palace manager after Tony Pulis resigned in August, less than 48 hours before the start of their Premier League season, said he had "made an inquiry" afterwards.
"I felt it was out of order," Warnock told a news conference. "I made an enquiry after the game because I was disappointed."
Asked if he felt the announcement had affected the outcome, or the performance of either team, he added: "I think that's why they threw the last goal in -- so they didn't go to Man City away..."
Palace, who finished 11th under Pulis last season after languishing at the foot of the table in November, are 15th and entertain seventh-placed promoted Leicester City, who beat Manchester United 5-3 last weekend, on Saturday.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
(Reporting by Tim Collings; editing by Toby Davis)
