Speaking ob Bas' injury Reading physio Jon Fearn told readingfc.co.uk: "It's been a week since his injury so we've sent him to a specialist. We'll see how it goes in the next week or so.
"There's a chance that he's sustained some structural damage - he's had a scan done but it's inconclusive. We'll see how he progresses with conservative treatment."
The Royals physio had previously said, around the time of the injury: "It looks like he's hyper-extended his knee and jarred the joint - there's no cartilidge damage or cruciate damage taht I am concerened about. Everything seems stable but he might be stiff for a few days.
"At best he'll be out for maybe one or two days - at worst three of four."
Meanwhile, centre-backs Adi Viveash, Adrian Whitbread and Ricky Newman are all expected to return to training shortly after suffering minor injuries.