Ferguson working on best striking options

Wayne Rooney's return from a gashed thigh in Wednesday's Capital One cup win over Newcastle opens up the possibility of Ferguson being able to field his perceived number one forward pairing for the first time this season when United entertains Tottenham Hotspur on Saturday (Sunday 2.30am AEST).

On ability and price tag alone, Rooney and Robin van Persie deserve first chance to operate in tandem.

However, there can be no guarantees.

Shinji Kagawa has impressed after his arrival from Borussia Dortmund, while Danny Welbeck emerged as England's attacking spearhead at EURO 2012.

And owing to Javier Hernandez's eye for a goal it is easy to see why Ferguson is unwilling to make any promises.

"It is early doors but at the moment I don't know where I am going in the sense of what my best partnership will be," said Ferguson.

"Probably the strongest part of the club will be in the striker department.

"It (Van Persie's arrival) should give everyone a push.

"Danny Welbeck is in the same position as Javier in that they are not the first team choices at the moment.

"That doesn't mean to say it will stay that way because competition is always healthy and them being the kind of young lads they are will be desperate to establish themselves.

"That is what competition is. We had it in 1999."

The Treble-winning quartet of Andy Cole, Dwight Yorke, Teddy Sheringham and Ole Gunnar Solskjaer have gone down in United folklore for their exploits as a unit.

But a true gauge of what Ferguson has at his disposal just now will not be known until Rooney and Van Persie actually begin to play together.

Even then, it may take a bit of time given Rooney's short pre-season was followed by that injury against Fulham, whilst Van Persie arrived at Old Trafford from Arsenal with only one outing under his belt.

"Wayne has had a great training programme in the time he was off. He was never out of the gym to begin with," said Ferguson.

"In the last two weeks he gradually got into the football part and started getting his timing back.

"Now he has to get through that period when he needs game time.

"It is like Van Persie because Robin has still got a bit to do.

"Against Liverpool, most of the other players had 10 or 12 games under their belt."

Yet, due to his massive strength in depth, Ferguson is nowhere near as bothered by any fitness issues further forward as he is by those at the back.

With Phil Jones and Chris Smalling already sidelined, seven days ago Ferguson expressed the hope Rio Ferdinand, Jonny Evans and Nemanja Vidic would remain fit to see United through its present troubles.

Two days later, Vidic missed the English Premier League win at Liverpool complaining of tightness in the knee he ruptured his cruciate ligaments in last December.

Forty-eight hours after that Vidic was being condemned to another two months on the sidelines after further surgery.

Yet Ferguson admits he was not entirely surprised by the chain of events.

"I don't think he was ever 100%," said Ferguson.

"I noticed a couple of times in training that he was limping a little bit. Then he started feeling tightness in his knee.

"He wanted to carry on and in that situation that is what tough guys can do.

"Obviously the main operation was to correct the cruciate but when you do cruciates there is always the danger that the cartilage or meniscus is damaged also and that was the case."

So now United must wait for its captain to get fit again, with Smalling set to be the first man back in action, sometime next month.

It is not the first time in recent years Ferguson has had his defensive resources decimated either.

"It is not easy to deal with injuries," he said.

"The difficulty is for our medical staff to make a decision as to when players are ready to come back.

"The worst that can happen is if you try and rush them back they get a training injury.

"That is unthinkable nowadays and that is what we are trying to avoid."