Newcastle United manager Alan Pardew has revealed striker Shola Ameobi will be out for four to six weeks with a hamstring strain.
Ameobi, 30, was a second-half substitute in Saturday's 1-0 home win against Wigan Athletic, and has made seven appearances this season.
"He felt something after about three minutes of coming on, but still played on," Pardew told BBC Look North.
"He'll be a loss to us and I think our fans will see that now."
The former England Under-21 international has been used as a substitute in three of his six Premier League appearances so far, as five-goal Demba Ba and Leon Best have been paired in the last five games.
However the Nigeria-born forward proved his value earlier this month with his only goal of the campaign, firing the equaliser in the 2-2 draw with Tottenham Hotspur at St James' Park to maintain the club's unbeaten start.
Since joining the club's academy as a 13-year-old, Ameobi has gone on to make 310 appearances in all competitions, scoring 71 goals.
He will now miss matches including the Magpies' Carling Cup fourth round tie against Blackburn Rovers on Wednesday.
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