United will merely be looking for survival this term, it is more than 40 years since they last competed in the second tier of English football and are up against clubs with spending power way beyond what is available at Glanford Park.
Charlton are aiming at the other end of the scale, they are gunning for an immediate return to the Premier League after relegation last season - and have cash available from the big-money sales of players like Darren Bent, Luke Young and Dennis Rommedahl.
And Weaver, who joined on a free transfer Manchester City this summer, insists his side have the quality to win promotion this term.
"I've gone up from this division a couple of times with Man City," said Weaver.
"And with the players we've got I'm convinced that we've got enough to get us straight back up.'"