The Dutch sharp-shooter has enjoyed a stellar start to his United career and took his goal tally to 11 in 14 games when he began the Red Devils' latest comeback in Braga on Wednesday. Yet Van Persie's contribution, after he had started on the bench, raised question marks over United's ability to perform without him.
The United boss does not view it as an issue though, and he said: "I don't think it's a problem relying on Robin. Last year, we lost (the title) on goal difference. I don't expect us to lose on goal difference again."
Ferguson's team have won every game in which the 29-year-old has scored on their rise to the Premier League summit and qualification for the Champions League group stages with two games to spare.
"Van Persie is experienced," Ferguson added. "He had eight years at Arsenal and that helps. He has come to us at the right time."
"The way Javier has started this season, I'm certain he'll get to 20 goals plus," said Ferguson. "Wazza will get there too, he'll get 20 goals plus I'm sure. It's a healthy combination we've got there."
A visit to Aston Villa on Saturday could well bring more cheer for United. In 16 Premier League trips since their last defeat, United have won 11 and drawn five against the Midlands giants, the side Ferguson pipped to win the first of his 12 titles in 1993.
Since then, Villa's fortunes have faded, but Ferguson said: "It is a daunting task as Villa are not where everyone expects them to be. Paul Lambert has done well as a manager and is still young. But it does take time to change teams and you wonder if the managers changing has a big effect on the playing standards of the team."
United will be without Nani with a tight hamstring but are hopeful of Jonny Evans' recovery from a groin problem, which would mean Ferguson does not have to force Chris Smalling back into action so soon after making his season's bow in Braga.