Fulham boss Mark Hughes said Manchester United can win the Treble this season after watching them defeat his team.
United are 10 points clear in the Premier League, lead Chelsea after the first leg of their Champions League tie and are in the FA Cup semi-final.
"They could win everything," said former United striker Hughes.
"They are ticking games off and when you get to this stage of the season, they have been here, understand what needs to happen and what it takes."
United won the Treble in 1999, defeating Bayern Munich in a dramatic Champions League final, Newcastle in the FA Cup final and finishing one point ahead of Arsenal in the league.
"It is a big ask," added Hughes of United's chance of repeating the feat. "Manager Sir Alex Ferguson would say himself it is very difficult to do.
"But trust me, it is something they will try to achieve. Good luck to them."
Ferguson made eight changes to the side that defeated Chelsea 1-0 in the first leg of their Champions League quarter-final at Stamford Bridge on Wednesday for Saturday's league match against the Cottagers at Old Trafford.
But it did not knock United out of their stride as Dimitar Berbatov and Antonio Valencia scored first-half goals as the home team ran out comfortable 2-0 winners.
"It was a result but I wouldn't say it was a job well done at all," said Ferguson.
"We were a bit casual and lackadaisical. In the first half we played some very good football and could have scored a couple more.
"But we became wasteful with our possession in the second and might have suffered for that."
United have six league fixtures left and take on rivals Manchester City next Saturday in their FA Cup semi-final at Wembley.
"Winning is the name of the game right now," added Ferguson.
"There were no injuries and I was able to rest a few players against Fulham. Everybody has come through fine."
Valencia scored United's second with a close-range header after 32 minutes and was replaced by Michael Owen with 20 minutes of the match remaining.
"Valencia is a marvellous footballer," said the United boss.
"We chose the right time to take him off and get him fresh for Tuesday. He will have an important role to play then."