Fed Blood Rule - Runners & Subs

[teebob21]

I need help on the Fed blood rule (3.3.10 I think). My kids have "helped" me misplace my rulebook somewhere here in my office, and the answer I need is not in the case book.

Situation: BR hits a double and skins her knee badly sliding into 2B. It cannot be stopped/cleaned up in a reasonable amount of time. Offensive coach puts in a runner (R2) off the bench.

(1) Is this a substitution?
(2) Can R2 enter the game for a different batter later, or do normal sub rules apply?

Thanks.