The 30-year-old forward has come in for criticism in recent days following United’s surprise 2-0 defeat by Olympiacos in the Champions League last 16 on Tuesday.
If he leads the line better, they would be a much more all-round team
Van Persie spurned a glorious opportunity to score a vital away goal late in the second half in Greece and after the game appeared to criticise David Moyes’ tactics.
But former Crystal Palace manager Warnock feels that it is up to the striker himself to help reverse his side’s ailing fortunes.
“I know what Robin van Persie’s said but, if he leads the line better, they would be a much more all-round team,” Warnock told talkSPORT.
“If he put in more effort up front and chased more lost causes, like Wayne Rooney does, then it’s easier for his midfielders and his defenders to push up.
“The first line of your defence is your attack and I don’t think Van Persie put in a shift.”
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