By Chris LaBate

WBA junior welterweight champion Amir Khan is not completely sold on Robert Guerrero's reported left should injury. It was announced on Thursday that Guerrero suffered a left shoulder injury in training camp and was forced to withdraw from his upcoming fight with Marco Maidana, which was scheduled for August 27th in San Jose, California.

Maidana and Guerrero were fighting for the WBA's "regular" junior welterweight title. Maidana, who won the interim-title in April, became the "regular" champion when the sanctioning body made Khan the "super champion" at 140-pounds. 

Khan, speaking to his Twitter followers, cast a shadow of doubt on the injury and made an allegation that Maidana paid Guerrero money to step aside in order to force a Khan-Maidana rematch. Maidana has been chasing Khan since their "Fight of The Year" bout in 2010. Khan is scheduled to return on December 10; no opponent has been set.

"No injury, I reckon Maidana paid off Guerrero [with] step aside money, so he can become the WBA [regular] champ because I have moved up as WBA super champ," Khan wrote.