Sources in both rappers' camps tell us Meek had Sunday night marked down on his calendar -- knowing full well Drake was scheduled to be behind enemy lines ... performing in Meek's hometown. We're told Meek's crew put out calls to several nightclubs asking them to turn down Drake if he wanted to throw an after-party.
Meek's camp also put out calls to several hundred of their homies in town, and asked them to make a show of force at the Wells Fargo Center. Things really got heated when their crews contacted each other directly -- Meek's team warning Drake's that there better not be any disrespect when they got to Philly.
We're told the warning only pissed off Drake ... and reignited the beef. This is exactly why he called Meek a "p****" on Saturday night ... and then ripped into him even harder in Philly.
For what it's worth -- Drake did NOT party in town after the concert. It's unclear if that's because Meek's blockade was successful, or if Drizzy just chose to get the hell outta Dodge ... with all his bodyguards nearby.