The 22-year-old joined the Red Devils from Molde – the former club of United hero and reserve team coach Ole Gunnar Solskjaer - in July 2009 but remained in Norway while awaiting a work permit.
Diouf caught the eye of the Old Trafford outfit with his impressive goals to games ratio – netting 29 times in 63 appearances.
And having had his work permit granted in December - making him available to join the United squad from January 1 - he featured for the first time in the 1-1 draw at Birmingham City on Saturday, replacing Paul Scholes after 81 minutes.
The pacy striker is hoping to provide an extra dimension to United's front-line alongside Wayne Rooney, Dimitar Berbatov and Michael Owen and help them overcome the mixed run of results that has handed the advantage back to table-toppers Chelsea.
And Ferguson has revealed that he is pleased with what he has seen so far.
"He’s adapted very well to our training regime and has looked very impressive,” Ferguson told Inside United.
“He’s quick, very good in the air and a good striker of the ball. Overall, he’s a really good centre-forward and he’ll play a part."
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