Sheffield United will have to finish their season without striker Oli McBurnie, who has suffered a fracture in his foot.
McBurnie was injured during last weekend's defeat against Arsenal at Bramall Lane, and given the time it would take to complete rehabiliation from the injury his place in Scotland's squad for the rearranged 2020 tournament is now in doubt.
Heckingbottom has now lost two forwards in quick succession after United captain Billy Sharp underwent surgery on a thigh problem this week.
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"He (McBurnie) has got a stress fracture in his fifth metatarsal so we've lost two forwards, which isn't positive," said Heckingbottom before Saturday's trip to Wolverhampton Wanderers.
Sheffield United are bottom of the table with 14 points from 31 games and relegation will be confirmed if they lose to Wolves and Newcastle United avoid defeat against West Ham United.
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