"We'll know once Dr. Lowe sees him," Rangers assistant general manager Mike Daly said.
Hamilton underwent reconstructive surgery on the knee on June 8 of last year. He was cleared medically in December and signed a Minor League contract in January. Hamilton came into camp saying he was feeling great but the knee started acting up on him and he felt a sharp pain running. He was examined by Lowe last week and given a PRP injection.
But the injection didn't help.
"Josh felt and Dr. Lowe felt that he needed to go back down and get an evaluation," Daly said.
If Hamilton does undergo surgery, it could set him back four to six weeks. The best case scenario would be start the season on the disabled list and get significant time in the Minor Leagues before he is an option for the Rangers. Hamilton missed all of last season because of the knee.
There is also the possibility Hamilton might not be able to play again.
"I don't think anybody wants to take it to that extreme," Daly said. "Josh has stated that he wants to play. That's why he is in camp. He wants to play and we want him to play. We'll see what happens after Dr. Lowe looks at him."
T.R. Sullivan has covered the Rangers since 1989, and for MLB.com since 2006. Follow him on Twitter @Sullivan_Ranger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.