If United are to stop the Italian from leading City to Wembley in only his first weeks in charge, they will have to find both the resolve and inspiration that were sadly lacking at the Eastlands cauldron. It will be of scant comfort to Ferguson that both of Tevez' goals were virtual gifts from the United defence. Even more concerning will be the fact that on a night when he named arguably his strongest XI available, it wasn't enough to cope with their blue neighbours.
Not even an opening goal from Ryan Giggs after 16 minutes could spoil the party that City have been desperate to throw since inundated with Arab oil.
For their newfound wealth, City have hardly had United sheikh-ing on the pitch losing all three derbies since the arrival of Sheikh Mansour. That was until this game.
Tevez is their crown jewel if only for the fact that he was willed away from the red half of Manchester last summer.
And his two goals a penalty just before half time and a close range header on 65 minutes afforded City victory in the most perfect manner, as far as their long-suffering supporters were concerned. Chant
Fergie, sign him up, Fergie, Fergie, sign him up, the home crowd crowed, mimicking the chants from Old Trafford for much of last season.
But it won't just be the scorer of the goals that will have irked Ferguson rather the manner in which they came.
Schoolboy defending from Rafael wrestling Craig Bellamy into the penalty area three minutes before half time, provided Tevez with the perfect opportunity to score from the spot and he duly obliged.
Then slack defending inside their own box with 25 minutes to go allowed Vincent Kompany to clip a short cross to the Argentine, who stole in ahead of his good friend, Patrice Evra, to head past Edwin van der Sar.
If nothing else, it has set up an edge of the seat second leg at Old Trafford in a match that Ferguson dare not lose. If there were any doubts about how seriously the United manager was taking this derby double-header, if not the competition as a whole, he answered them in emphatic fashion with his team selection.
Naming arguably the strongest side available to him, he made it clear he will do his level best to ensure City's 34-year trophy-less run continues.
Whether he would have fielded the same team had United not been knocked out of the FA Cup at the third round stage, will remain a point of conjecture. But the fact that the draw threw up a semi-final against their cross-city rivals meant Ferguson had no choice but to send out an XI capable of toppling Mancini's men.
That certainly looked the case when Giggs tapped home Antonio Valencia's cross from close range, only for Tevez'double to eclipse it.
But even if City have one foot in the final, the fervour with which United went in search of an equaliser gave a tantalising glimpse of what can be expected in the second leg.
Wayne Rooney, Michael Owen, Valenicia and Mame Biram Diouf all came close to leaving this tie on a knife-edge at the halfway stage. What is your verdict on the game? Have your say.