LONDON (AP) -- Manchester City has already won one major battle ahead of today's Premier League derby: convincing Manchester United manager Alex Ferguson that it is a force to be taken seriously. Ferguson initially dismissed City as "noisy neighbours" following a 2008 takeover by Abu Dhabi investors but now says that the rivalry is becoming as important as that with its traditional enemy Liverpool. "If we're going to be contesting with them for the league titles regularly -- and I think we will be -- it will become almost as important as the Liverpool derbies," Ferguson said. "Maybe not in terms of the emotions; the Liverpool-United games are emotional. But certainly in terms of importance this supersedes Liverpool at the moment because City are our direct opponents. "Manchester City are up against us to win titles. We have to focus on the team who can affect our progress in terms of winning the league." United overtook Liverpool as England's most successful club with last year's record 19th league title. City would have to win the Premier League every season until 2029 to relieve its local rival of that status but it can take a huge step forward with the victory that would draw it level on points with United at the top of the Premier League. But City manager Roberto Mancini has remained calm, pointing out that he is used to these types of situations, even if City isn't. While Mancini won three league titles as manager of Inter Milan and another two as a player, City has not been English champion since 1968. If it wins, City's superior goal difference would make it a firm favourite for the title. That is an entirely plausible outcome given that City has already won 6-1 at Old Trafford this season, handing Ferguson his worst defeat in 26 years at United. City also knocked United out of the FA Cup semifinals last season on its way to ending a 35-year streak without a trophy. United beat City 3-2 in the season-opening Community Shield at Wembley and won at the Etihad Stadium by the same score in January's FA Cup third round. Both teams have thrown away the chance to take a decisive grip on the title race, most recently when United lost 1-0 to Wigan and then drew 4-4 with Everton after leading 4-2. City midfielder Gareth Barry said United's spell as leader and favourite had lifted the pressure from his team.