Sir Alex Ferguson has loaded the pressure onto Manchester City ahead of Sunday's climax to the Premier League title race, warning the City players that they could ruin the club's future if they fail to beat QPR.

379252 - Title failure could wreck Man City's future - Fergie

Ferguson is close to helpless in the defence of Manchester United's crown, knowing he almost certainly cannot stop City winning the league if they overcome QPR at The Etihad Stadium. All he has left is his famed mind games, and he has made one final attempt to influence the outcome of Sunday's action.

Such is the expectation for City to end their 44-year wait for a top-flight championship that Ferguson insists it would almost be embarrassing for the club's players to mess up.

Roberto Mancini's men could be on the cusp of an era of success - funded by the finances of their owners - but Ferguson warns that failure this weekend could leave City nursing a scar so deep that it could stay with them for years.

"City have got to win, but it's an enormous challenge for them, because the disappointment of losing the game would be unbelievable," Ferguson said.

"It's untold at this moment in time what affect it could have on them."

The pain of seeing United's neighbours take their Premier League crown would hurt Ferguson this weekend. But he insists the agony facing City if they capitulate under the pressure will be far worse.

"To win the league is not easy," Ferguson said. "Many people underestimate how difficult it is to win the league.

"It's fantastic for the neutral, fantastic for the media, but agony for both clubs, and more so for City if they lose it."