Closer Ratings

What exactly does a c-6 refer to?

I am aware that a r-2 means the relief pitcher can go 6 outs before getting tired, and that an r-1 means the pitcher can go 3 outs. What does C6 mean?

Thanks.

Basically a C6 can enter a game that is a save situation and go six outs before tiring.

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I am aware that a r-2 means the relief pitcher can go 6 outs before getting tired, and that an r-1 means the pitcher can go 3 outs. What does C6 mean?

Thanks.

I do not believe this is correct. I believe R2 means a reliever is less likely to become fatigued for one inning. (Any pitcher hit hard enough can become fatigued in any inning.) An R3 would have two semi-exempt innings, and an R1 would not have any.