Manchester United [Images] manager Alex Ferguson believes Wayne Rooney [Images] and Cristiano Ronaldo [Images] are poised to become the best players in the world.

Rooney, 18, has scored 15 times in his first season at Old Trafford while Portugal international winger Ronaldo, 20, has been outstanding in the English Premier League and Champions League.

"They are both fantastic," Ferguson told a news conference on Friday. "We are very fortunate to have two young players who I think in the next few years will be world-class players.

"I think those two will be the best players in the world, probably with Ronaldinho [Images] at Barcelona."

Rooney scored twice in United's 2-1 defeat of Portsmouth on Sunday which maintained the pressure on leaders Chelsea. He has scored 15 goals in 30 appearances since signing from Everton for 27 million pounds ($51 million) in the close season.

"Last week emphasised the form he is in and the improvement in him. Every week he seems to be adding something to his game," Ferguson said.

"He had a long break from the metatarsal fracture he had in the European Championships. He had 96 days without football and then he really missed pre-season so he was out for five months.

"It took us quite a while to get him to the sharpness and fitness he is at the moment. That was mainly through playing and the form he's in, he is not showing any signs of needing a rest."

BAD TREATMENT

Ferguson remains unhappy at the treatment Ronaldo gets from opposition players.

"The one thing it's telling you is that he is giving defenders problems. If they have to foul him and bring him down all the time, then it tells you he's doing something really well," Ferguson said.

United and Chelsea play away to teams threatened with relegation on Saturday with United hoping to beat Crystal Palace and narrow the six-point gap on the leaders who have an evening kick-off at Norwich City.

"It may make a difference and that's the point of winning this game tomorrow, getting to a position where we are only three points behind them," said Ferguson.

"For our confidence, it does it no harm. Whether it can affect Chelsea, we will have to wait and see." Chelsea have a game in hand over United and Arsenal [Images] in third place.

Gary Neville misses United's trip to Selhurst Park with an ankle injury. Ferguson hopes the full-back will be fit for Tuesday's Champions League game at AC Milan, who lead 1-0 after the first leg.

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