LONDON (AP) -- Manchester City's second straight league win at Old Trafford likely won't be enough to make a difference in the Premier League title race.
Substitute Sergio Aguero slalomed through the defense to score the go-ahead goal in the 78th minute, giving City a 2-1 derby win at United on Monday night that cut the defending champion's deficit to 12 points with seven games left.
"We showed we deserved to stay closer to the title but it is finished," City manager Roberto Mancini said, maintaining his stance of the past three weeks.
Seeking a record 20th English league title, United (25-4-2) lost a league match at home for the first time since a 3-2 defeat to Tottenham on Sept. 29. Overall, United had been 16-0-2 in the league since a 1-0 defeat at Norwich on Nov. 17.
"You don't want to lose a derby game, but we're OK," United manager Alex Ferguson said. 'It is easy to see why these were the best two teams in the country; the evidence was there tonight."
James Milner gave City (19-4-8) the lead with a 51st-minute shot that deflected off Phil Jones after Gareth Barry stole the ball from Ryan Giggs and cut back a pass to Samir Nasri.
City captain Vincent Kompany inadvertently deflected Jones' header into his own eight minutes later for an own goal. Aguero replaced Nasri in the 71st, and he collected Yaya Toure's short pass before dribbling through the defense and beating goalkeeper David De Gea to the near post.
"If you look at the history of this club, we always make things difficult for ourselves," Ferguson said.
ROME (AP) -- Hernanes put Lazio ahead and failed to convert a penalty kick in a 1-1 tie against Roma in the city derby.
Hernanes gave Lazio the lead in the 16th with a 25-yard volley and was wide with a penalty wide in the 48th. Hernanes fouled Miralem Pjanic, giving Roma a penalty that was converted by 36-year-old captain Francesco Totti in the 56th minute.
Lazio finished a man short after Giuseppe Biava received his second yellow card in the 69th.
The match was marred by clashes outside Stadio Olimpico before kickoff, with at least four fans stabbed and an ambulance attacked.
Lazio (15-10-6), which had won the previous three derbies, is sixth, 20 points out of first and three points ahead of seventh-place Roma (14-11-6).
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