From The Collaborative International Dictionary of English v.0.48:
Pit \Pit\, v. t. [imp. & p. p. Pitted; p. pr. & vb. n. Pitting.] 1. To place or put into a pit or hole. [1913 Webster]
They lived like beasts, and were pitted like beasts, tumbled into the grave. --T. Grander. [1913 Webster]
2. To mark with little hollows, as by various pustules; as, a face pitted by smallpox. [1913 Webster]
3. To introduce as an antagonist; to set forward for or in a contest; as, to pit one dog against another. [1913 Webster]