The Red Devils stretched their advantage to six points thanks to Sunday’s dramatic 3-2 victory over champions Manchester City at the Etihad Stadium, with bookmakers slashing the odds of United prising the title from their local rivals to 8/15.
Struggling Sunderland travel to Old Trafford on Saturday for what is the first of five Premier League games in 18 days for Ferguson’s men.
And the Manchester United boss is hoping his side can steer clear of injuries through a crucial period for the league leaders.
“I’m happy with six points and it’s City’s challenge to try and catch us,” Ferguson told a news conference on Friday.
“There are a lot of big games to come and I don’t think six points is such a healthy lead. We threw a league away against Arsenal years ago, in 1998.
“We had a catalogue of injuries and that is the key. If you’ve got 20-odd players in your squad, you’ll work on two players not being available each week. If we can keep it to that, I’ll be delighted because it will give us a better chance.
“There are a lot of key issues in the second half of the season anyway, plus the fact you’ve got to get through this Christmas programme. Navigate that and if we’re still top of the league then we’ll be delighted.”
Ferguson also confirmed that captain Nemanja Vidic will be included in Saturday’s squad to face the Black Cats after his lengthy lay-off, but Jonny Evans (hamstring), Nani (hamstring) and Shinji Kagawa (knee) all miss out.
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