Swansea are set to be without Angel Rangel for up to month after the right-back damaged ankle ligaments.
The 29-year-old landed awkwardly during the first-half of Swansea's goalless draw against Aston Villa on Sunday.
Scans revealed the Spaniard has damaged his ankle ligament and he is expected to be out for four weeks.
Wales Under-21 captain Jazz Richards, who replaced Rangel against Villa, is likely to deputise against Blackburn on Saturday.
Meanwhile Swans striker Danny Graham is hopeful of facing the Premier League's bottom side at Ewood Park.
The former Watford player limped off the field against Villa suffering with an ankle and Achilles injury.
But Graham, who has scored four league goals so far this season, is desperate to be fit for the match.
"I'm still hopeful of making Saturday," Graham told Swansea's official website. "I think the next 24 hours will be crucial once the swelling has gone down.
"Although it's still early in the season, Saturday's game is going to be massive.
"If we can pick up a win at Ewood Park it will move us 10 points above Blackburn, which will be a good cushion to have going into the busy Christmas and New Year period. It's a game I want to be fit for."