A damaging defeat at Stockport County on Tuesday saw the club relinquish a two-goal lead to go home with nothing to show for their evening at Edgeley Park.
Port’s 3-2 loss means they are still seven points away from the top seven.
Watson thinks they may need to win eight - or seven and claim three draws - to have any chance of seeing their season extended.
“We’ve got 12 games left,” he told the club’s video service. “The challenge is now to take 24 points.
“If we do that we’ll be on 63 points and that might just be enough, who knows.
“If we took seventh place, would we be good enough to go and win three away games in the play-offs? Probably not at the moment but it’s one game at a time.
“We’ve got six home games left and six away. We really need to make Haig Avenue an enjoyable place to be at for those matches.”
Understandably, Watson wasn’t happy with the manner of the defeat at Stockport.
“You can’t ship three goals, not when you have taken a 2-0 lead,” he added.
“The game is played over 95 minutes, not 43 and that goal just before half-time has cost us.
“Until then we were looking excellent but we weren’t good enough to stop them getting their goals.”