Rondon played under Pellegrini at Malaga before leaving the Spanish club for Rubin 12 months ago, but he has been linked with a reunion at the Etihad Stadium.
Reports have claimed Rondon is one of the options under consideration by Pellegrini following the sale of Carlos Tevez to Juventus.
However, Venezuela international Rondon has brushed off the speculation after confirming there has been no offer from the Premier League club.
"The press sometimes come to conclusions from sources that nobody knows," the 23-year-old told EFE.
"The truth is that I have no formal knowledge about any of those clubs.
"Yes, we read and hear things in the press, it's talked about that there is possible interest, but until something is made formal, or there is something concrete, I can't tell you anything."
Meanwhile, reports in Argentina have claimed that City have shown an interest in San Lorenzo winger Julio Buffarrini, who would jump at the chance of such a transfer.
"If an offer arrives, and it's useful for San Lorenzo, we will analyse it," the 24-year-old told Mundo Azulgrana.
"Therefore, I have said to Marcelo Tinelli, the vice-president, that the only team that I would play for in Argentina would be San Lorenzo.
"I have heard about a possible interest from Manchester City. If I have to leave, I will do it very happily."