Van der Gun is struggling with a hamstring problem and has been missing since the beginning of January. But last Saturday's postponment against Watford has given him extra time to recover and he could be in the frame.
Craig Beattie has sustained a foot injury and he too is doubtful, although Paulo Sousa is much more hopeful the former West Brom man will make it.
Shefki Kuqi could be handed his first start in attack after making his Swans debut as a substitute at Coventry a fortnight ago, with Gorka Pintado potentially making way.
Joe Allen will be hoping to get the nod over Jordi Lopez in midfield but defender Albert Serran (hamstring) remains on the sidelines.
Kick-off in South Wales is at 1pm.