Forty years may have passed, but there is one topic that remains off-limits for Denis Law when discussing Manchester derbies. Law may be 74, but he is as sharp and engaging as ever in discussion. At a sponsor's event inside Old Trafford earlier this week, not far from where his statue stands outside the famous stadium, the conversation flows with the Manchester United hero until the subject of his controversial goal in the 1974 Manchester derby is raised. VIDEOS Scroll down to watch Denis Law believes Wayne Rooney and Robin van Persie are two of the world's best strikers Rooney (centre) will return to Manchester United's starting line-up after serving his three-match ban
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Denis Law is glad Wayne Rooney is fit for Sunday's Manchester derby
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United legend Law believes Louis van Gaal's side are building momentum
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Law stated he could not remember scoring the goal that sent United down
'It's an incredible boost to have @placeholder back,' Law added.