A draw was not enough to lift Liverpool out of 13th place and they ended the weekend 15 points behind United.
"Listen, the reality is we're a long way off in the league," Rodgers said.
"You don't need to be a rocket scientist to see the squad... These guys are giving me everything.
"We finished eighth last year. If we can improve on that, it'll be fantastic for us.
"That's the reality of where Liverpool are I'm afraid. But our young players will get better and better.
"We need one or two more players. That's our sixth draw, and a lot of those games we've come back into after going behind.
"But we need materials. If we can get one or two in January, we'll turn draws into wins."