SIR Alex Ferguson as thrown down the gauntlet to his three mainline strikers. The Reds boss is expecting a 20-plus goal return from Wayne Rooney after the England hitman opened his Premier League account - and wants the same from Dimitar Berbatov and Michael Owen. Rooney's first-half pounce won the champions their first opening day Old Trafford league match since 2006. Following his goal against Chelsea in the Community Shield at Wembley last week, it is a promising start for the 23-year-old. "Wayne's header was a good one but his follow up was quick. He reacted in the right way," said the United manager after Rooney seized on a rebound to beat top flight newcomers Birmingham. "Hopefully that gets him on the road, with his goal in the Community Shield last week, to a very significant total for us this season. "It is good if you have two or three strikers who can get you over 20 goals each. "Wayne is capable of more than 20. We are not asking the impossible from the boy. He can do that and hopefully he will." Summer free-transfer Owen and £30m club-record buy Berbatov are the other two Fergie is anticipating a 20-goal return from. Owen had an injury-time opportunity to kick-start his competitive goal account for the Reds but was denied by Birmingham's on loan keeper from City, Joe Hart. Michael Owen chance "It would have been fantastic for Michael," added Sir Alex. "It was a great save and when you see the replay it is a better save than you think. He will get his goal and once he does it will set him off on the road." United's slender 1-0 win was a throwback to last winter when the eventual title winners accumulated eight such scorelines. Ben Foster was the late hero for the Reds when he stopped a Christian Benitez chance and it got the 26-year-old back on form after an off-colour display against Chelsea at Wembley. "Ben had a fantastic save in the second half. He looked very comfortable and relaxed in goal," said Fergie. "He has learned from last week at Wembley. It was an unusual nervy performance from him in the Community Shield. We know he has got the ability and he proved that again. "A clean sheet is always a clear indication that as a team, you are going to defend right and I will take eight 1-0s every season. "I know it is not good for the nerves but this club is famous for that. Nobody gets an easy ride, the supporters, the staff, myself and the players. Nobody gets an easy ride. "We are always capable of taking it right to the wire and keeping the supporters on a knife edge. It is exciting though! "It was quite a long day because the way Birmingham set their stall out they were going to be very determined and resilient and hard to break down. That is understandable. They have come out of the Championship and are desperate to stay in the Premier League. "It was noticeable the amount of shots we had blocked in the game. I think Paul Scholes alone had four blocked." United had to start the Premier League campaign without three of their recognised first choice defenders. What do you think? Have your say.