Ferguson signed Robin van Persie from Arsenal for 24 million pounds in the off-season, and the Netherlands international has dazzled Old Trafford with 22 goals in just 28 appearances in all competitions.

Hernandez has responded with 14 goals from 24 games, while England duo Wayne Rooney and Danny Welbeck have also performed well this term, giving Ferguson a selection headache.

"It's a terrible dilemma when I've got that lad (Hernandez) there," he told reporters.

"Sometimes I leave him out to bring in Robin van Persie but, as I explain to him, we regard him so highly.

"He's a fantastic professional, unbelievable attitude to the game, never stops running or working and every training session's the same.

"So I'm really pleased for him and it's also good to see Wayne back scoring."

Hernandez's latest brace eased his side to a 4-1 win over Fulham in the FA Cup fourth round on Saturday, while they lead the Premier League table by five points ahead of a meeting with Real Madrid in the last 16 of the Champions League.

Next up though is a match at home to Southampton in the league on Wednesday, with Ferguson wary of the threat posed by the promoted team.

"(Southampton) played really well against Everton, who are at the top of their game and playing really well, so we're not taking anything for granted," he said, referring to the Saints' 0-0 draw at their St Mary's Stadium home last Monday.

"They should have won as they were superb and could have been five-up in the first half," he said.

"Tim Howard had a fantastic game, they hit the woodwork and Rickie Lambert missed a couple of chances."