No agreement has been reached in the Jeremy Piven grievance hearing.

Piven appeared Thursday at the session requested by the producers of "Speed-the-Plow," which the performer abruptly quit in December after his doctor said he was suffering from mercury poisoning.

But after hearing from both parties, a panel composed of Actors' Equity and Broadway League representatives were unable to reach the necessary unanimous decision. A joint statement issued by the union and the Broadway producers' trade association said "the producers have the right, as a next step, to proceed to arbitration."

The producers could not immediately be reached for comment.

Piven's spokeswoman, Samantha Mast, issued a statement saying: "Mr. Piven is hopeful that the producers will ultimately recognize that he did the right thing by listening to the instructions from his doctors ... who told him to stop the play immediately and undergo enforced rest, rather than continuing to perform and risk dire health consequences."

The 43-year-old Piven, the Emmy- and Golden Globe-winning star of HBO's "Entourage," departed the production of David Mamet's satiric comedy after his physician said he had high levels of mercury in his body, possibly from eating too much sushi.

"Speed-the-Plow" opened last October to generally enthusiastic notices and by the time the revival ended its limited engagement Feb. 22 at the Ethel Barrymore Theatre, it had recouped its $2.26 million production costs.

Three different actors _ understudy Jordan Lage, Norbert Leo Butz and William H. Macy _ followed Piven in the role of movie mogul Bobby Gould. Mamet's three-character play about Hollywood glamour, sex and power, also starred Elisabeth Moss of AMC's "Mad Men" and Raul Esparza.

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