Rooney and Van Persie are yet to start together since the former Arsenal captain’s £24m switch to United after the England striker sustained an injury in a 3-2 victory over Fulham.
In addition, Ferguson has Javier Hernández and Danny Welbeck to provide competition, and the Red Devils manager considers his forward options to be United’s strength at the moment.
“I think probably our strongest part of the club at the moment is the striking department,” said Ferguson.
“I think Welbeck and Chicharito have been doing really well and Shinji’s been terrific, he’s been settling in well. The combinations we have up front, I think are quite strong.”
Ferguson had Andy Cole, Dwight Yorke, Teddy Sheringham and Ole Gunnar Solskjaer to choose from in United’s unprecedented Treble-winning campaign in 1998/99.
The 70-year-old is hoping fierce competition for places will ensure United’s current strike-force are kept fully motivated, and as a result, the Red Devils can reap the benefits.
“It did a lot of good for Andy Cole and Dwight Yorke because they knew that Teddy Sheringham and Ole Gunnar Solskjaer wanted to play. And they did get a lot of football; I was able to change them around several times,” added Ferguson.
“It’s early doors of course but I don’t know what my best partnership would be because I haven’t seen Rooney and van Persie together.
“Wayne has to play games and get game time now. I think Robin has still got a bit to do as well in terms of game time because he missed the whole of pre-season. In the Liverpool match he was playing against players who had 10 or 12 matches under their belt.”
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