Peyton Manning
After rejecting the Dolphins, the race for Manning's services may be coming to an end pretty soon. Reuters

Injured Indianapolis Colts quarterback Peyton Manning had stem cell therapy in Europe before having a third neck surgery this month, according to a report.

Jay Glazer of Fox Sports reported Sunday that Manning had the controversial therapy, which isn't yet approved for use in the United States. Since Manning went ahead and had a third neck surgery, it is reported that the therapy didn't work.

Just before the start of the NFL regular season the 35-year-old Manning announced that he could not play in the Colts' opener.

To say I am disappointed in not being able to play is an understatement, Manning said in a statement before the start of the season. I simply am not healthy enough to play, and I am doing everything I can to get my health back.

Days later, it was reported that the veteran quarterback had another neck surgery that might keep him out for two to three months.

Manning reportedly decided to have the surgery after consultation with a half-dozen doctors who through the best option would be a one-level cervical neck fusion, whic he had. Manning already had surgery in May to repair a bulging disk.

According to the report, Manning had stem cell therapy in Europe in trying to avoid another surgery -- which could end his career of recovery and rehabilitation doesn't go well.