Alex Rodriguez's description on Tuesday of a drug called "boli" that the slugger said was procured in the Dominican Republic and led to his positive test in 2003 has raised question marks with anti-doping experts, according to ESPN.com.

The Web site contacted Dr. Don Catlin, who identified the drugs in the Bay Area Laboratory Co-Operative (BALCO) case, and Caitlin said he has never heard of a performance-enhancing substance called "boli."

ESPN.com also talked to convicted steroid dealer Kirk Radomski, who said he hadn't heard of it either.

"I have a pretty good screening device, but that's a new name," Catlin told ESPN.com.

Catlin also was puzzled by Rodriguez's claim that he had only injected one drug. In the original article that revealed Rodriguez's positive test in 2003, Sports Illustrated wrote that Rodriguez had tested positive for Primobolan and testosterone.

But Catlin told ESPN.com that it is "very, very unlikely" that a single injection could produce two positive tests unless tainted, which Catlin admitted is a possibility considering the drugs were allegedly purchased in the Dominican Republic.

"Primobolan is a separate and distinct chemical," Catlin told ESPN.com. "You identify it as a specific structure and we know how to do it. Testosterone has a separate and distinctly different fingerprint."