Frandsen blow for Bolton
Frandsen suffered the injury in the 1-1 draw with Chelsea over the weekend, lasting just 45 minutes before hobbling off.
"Losing Per is another blow because he has been doing so well this season," said manager Sam Allardyce.
"But at least it is only a small tear to his hamstring and he should only be out for about ten days."
Meanwhile, French schemer Youri Djorkaeff has insisted that Celestine Babayaro did elbow him in the draw at the Reebok Stadium, amid suggestions that Chelsea may appeal against the sending off of the Nigerian.
"I got an elbow. He was stupid to do what he did," declared Djorkaeff.
"The ball was in the air and he elbowed me. The referee did very well."