Initially it was thought the Raiders star could miss up to eight weeks after going down in the dying minutes of Canberra's 40-18 loss to North Queensland last weekend.
But scans results have cleared the five-eighth of an ankle syndesmosis injury and any damage to his cartilage or tendons.
It means Dugan could be ready to take the field again for the round 20 clash against the Sharks on July 22.
It's been a dire year for the Raiders when it comes to injuries, with captain Terry Campese and Brett White ruled out for the season and four others still on the long-term injury sidelines.
But in more good news, forward Joel Thompson was cleared of a suspected broken hand, although ligament damage could still rule him out of Monday night's home clash against St George Illawarra.
Thompson, Dugan and Trevor Thurling were three Raiders who went down in the Cowboys game, with Thurling set to miss at least six weeks with damage to the AC joint in his shoulder.