Yankees closer Mariano Rivera has blood clot in calf

(CBS/AP) NEW YORK - Mariano Rivera has a blood clot in his right calf, the latest health problem for the longtime New York Yankees closer who tore a knee ligament last week while shagging fly balls during batting practice.

Rivera is on blood-thinning medication intended to dissolve the clot and says he is OK, though he was scared when he received the diagnosis. He needs to spend at least a week or two strengthening his knee before he has surgery to repair his torn anterior cruciate ligament — but he says that would have been the case regardless of the blood clot.

The 42-year-old Rivera, baseball's career saves leader, says he will do whatever it takes to return next season. He says he was leaning toward pitching in 2013 even before the injury.

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"I'm coming back. Write it down in big letters. I'm not going out like this," he said last week. "This has me thinking, I can't go down like this. If it takes two, three, four, five, seven more (seasons), whatever it takes."