Mariano Rivera has been taking blood thinners ever since he learned about a blood clot in his right calf. The Yankees closer said the clot will not delay the date of the surgery, which still has not been set because he needs to rehab the knee and get some range of motion back before going under the knife. Rivera is done for the 2012 season after tearing his ACL and meniscus last Thursday in Kansas City. He expects the surgery to happen in the next couple of weeks and added that doctors weren't able to tell him whether the injury led to the clot or if it was there before he suffered the injury.