Swansea's promotion bid has taken a blow with the news that captain Gary Monk has been ruled out for three weeks with a calf strain.
The defender limped out of the 1-0 win over Middlesbrough on Sunday and will now miss this weekend's game against Doncaster.
"We received the scan reports back today," Swans physio Kate Rees told the club's official website.
"It confirmed a small calf strain that could keep him out for two to three weeks."
Brendan Rodgers will have further defensive worries as Swans vice-captain Alan Tate is suspended for the trip to the Keepmoat Stadium.
The defender will serve a one-match suspension after picking up a yellow card in his last outing against Boro.