PLAYOFF POP:

San Francisco Giants slugger Will (The Thrill) Clark has his own theme song (if you call his answering machine, it plays B.B. King’s “The Thrill is Gone”). Not to be outdone, the Chicago Cubs (the Giants play-off rivals) have a theme of their own. Rhino Records is rushing out a 12-inch single called “The Cubbies Are Rockin’,” a rap celebration of the Cubs’ prowess by M.C. Gary and D.J. Barry (AKA veteran musician Barry Goldberg). The song’s lyrics go in part: “Walton and Smith, man, they got the speed, with Sandberg and Grace what more do we need, Bielecki and Maddux firing away, Sutcliffe on the mound, what more can we say . . . “ The flip-side is “The Addison Sheffield Shuffle,” a tribute to a pair of streets adjacent to Wrigley Field. . . . And on the blues-front: National Public Radio’s “Bluesstage” debuts Tuesday at 11 p.m. on KPCC-FM, featuring a series of live R&B; recordings, beginning with a Dr. John show from the Village Gate.