The MMA education of Roger Gracie has hit a roadblock.

Sherdog.com has learned that the upstart Gracie has been forced to pull out of his bout with Travis Wiuff, scheduled for Sept. 28 on Sengoku's forthcoming middleweight tournament opener at Yoyogi National Stadium First Gymnasium in Tokyo. The grappling phenom turned MMA prospect has sustained a rib injury in training that has forced his withdrawal.

Gracie's management confirmed the injury and withdrawal to Sherdog.com Wednesday morning.

On Sept. 8, Gracie was sparring when he took a hard kick to the ribs. After being examined by renowned physiotherapist Dr. Kevin Lidlow, who has previously worked with the British Olympic team, Gracie was diagnosed with an intermuscular tear to the intercostal muscle between the sixth and seventh left ribs.

Gracie is currently undergoing physiotherapy, and Lidlow has advised the grappling kingpin that he should not train for at least four weeks, at which point he will be reassessed with the possibility of resuming light, controlled training.

Gracie's bout with the well-traveled Wiuff was to have been his third pro MMA bout. The winner of five straight BJJ world championships, Gracie made his MMA debut in December 2006, submitting hulking heavyweight veteran Ron Waterman. After signing with Sengoku in early 2008, Gracie returned to the ring for the promotion's second card in May, where he notched a first-round submission over Yuki Kondo.

World Victory Road, Sengoku’s parent company, is expected to officially announce Gracie's withdrawal from the card Thursday, and may announce a replacement opponent for Wiuff at that time.