The England skipper is expected to be sidelined for six weeks due to a knee injury which the 30-year-old suffered during United’s 2-1 loss to Sunderland on Saturday.
Martial has been utilised as a winger by United manager Louis van Gaal for much of the season to accommodate Rooney in a centre-forward position.
However, the United captain’s injury setback means Van Gaal could play Martial in his orthodox striker role in the absence of Rooney.
Speaking to the Daily Mail, former Arsenal defender Keown admits that he is intrigued to see whether Martial can shoulder the extra responsibility.
“Of course there are always people who profit from an injury and I’m excited to see Anthony Martial play through the middle,” Keown said.
“I’ve been extremely impressed with him. There’s a bit of an arrogance in his play and he looks like he knows how good he is. But he needs that United mentality of: ‘You cannot have a bad game in a Man United shirt.’
“It’s now a question of whether he has got the appetite to carry that responsibility, because he certainly has the ability.”
Martial has scored seven goals in 21 Premier League appearances in his first season in the English top flight.
The France international moved to the Red Devils in a £36m deal from Ligue 1 side Monaco last summer.
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