Manchester United boss Louis van Gaal refused to be drawn on the form of Wayne Rooney and said he is fed up with being asked about it.
United were held to a goalless draw by rivals City at Old Trafford on Sunday in the 170th Manchester derby, a result which steered Manuel Pellegrini's side back to the top of the Premier League.
Van Gaal deployed Rooney as a lone forward and shifted the in-form Anthony Martial onto the left despite the Frenchman's impressive goal scoring form.
Rooney, who turned 30 on Saturday, failed to manage a single shot on target against City, and his only shot in the whole game was blocked in a rather anonymous performance, with United's best chances falling to Jesse Lingard and Chris Smalling late on.
The United and England captain has scored just twice in the Premier League this season and made the fewest touches of the ball than any of his team-mates during the derby with City.
He also produced no key passes, touched the ball once in City's 18-yard box and lost possession 28 times - more than any other player.
Van Gaal, however, was in no mood to discuss Rooney's form following the draw and insists he will no longer answer questions on the topic.
"I have to talk every week about Rooney, why?" the Dutchman said.
"You have your opinion - write it. I don't give any more answers about Wayne Rooney. I am sick of them."
In fact, United failed to muster a single shot in the first half of a Premier League match for the first time since the 2003-04 season.
United also struggled to create any clear-cut opportunities during the 1-1 draw with CSKA Moscow in the Champions League on Wednesday night and were indebted to Martial's second-half equaliser to salvage a point.
Van Gaal revealed he urged his United side at half-time on Sunday to try their luck from distance as they went in search of victory over a City side missing their two star men Sergio Aguero and David Silva.
"We know we didn't create so many chances because it is difficult how they have played, so organised, so on the counter-attack," Van Gaal added.
"That is like the game against Moscow, the same, also organised but it says something about the strength of Manchester United these days.
"But I have said at half-time we can also shoot from outside the box, you don't have to combine in the 16-metre area. Try your luck that way. That was my remark, you can shoot from outside the box. Now you can shoot, why you don't shoot?"