Now that “Luck” is off HBO’s schedule going forward, the pay cabler may have to rethink its 2013 programming slate.Luck07

The horseracing drama, which was given a second-season renewal almost immediately after the first season began earlier this year, would have likely returned next January if the show had not been canceled. In the new paradigm, however, HBO execs will probably have to fill that first quarter drama slot rather than have a gaping hole that could last months if “Luck” is not replaced.

Though nothing has been officially greenlit, of the five dramas that HBO currently has in rotation, there is a high certainty that “True Blood,” “Boardwalk Empire” and “Game of Thrones” will be back in 2013.

“Game of Thrones,” set to make its season debut April 1, was a huge hit for the pay cabler in 2011 and looks to be a longterm player. “Boardwalk Empire” has both ratings and cachet, and vampire fave “True Blood” — although showrunner Alan Ball won’t be actively involved on the show at that point — has always drawn a big audience.

That currently leaves two other dramas that are set to go this year: a third season of David Simon’s New Orleans saga “Treme” and Aaron Sorkin’s freshman series “The Newsroom.”Treme11_49

“Treme” has never been a ratings grabber, but neither was Simon’s Baltimore epic “The Wire,” and that ran for five seasons. And, including miniseries “Generation Kill,” HBO has proven that it enjoys being in the David Simon business.

With Sorkin in charge, “The Newsroom” has plenty going for it. Series, about the beind-the-scenes workings of a cable news network, stars Jeff Daniels, who rarely ventures to the TV side, and fans of Sorkin’s NBC staple “The West Wing” may sample the show as well.

If “Boardwalk Empire” repeats its 2011 sked dates — when it ended on Dec. 11 — HBO might be without a drama for three or four months, from mid-December through late March or early April.

That could be difficult to swallow for the pay cabler, which consistently needs top-quality original programming to give viewers the impetus to write their monthly subscription check. Especially at HBO, comedies rarely generate as much audience enthusiasm and chatter as dramas, and being without a drama on the air for that long could ultimately hurt the bottom line.

The unexpected “Luck” departure — HBO made the decision to cancel the show Wednesday after a third horse had died and there was no assurance, despite the best safety precautions, that it wouldn’t happen again — could work to the benefit of both “Treme” and pilot “The Corrections.”The_corrections_l

Though a decision has not been made on “The Corrections,” which is based on the Jonathan Franzen bestseller and is being adapted by writer Noah Baumbach, HBO might want to greenlight the series and get the production up and running as soon as possible. If it couldn’t duplicate the schedule of “Luck” and be on the air starting in January, HBO could shift another series to January and make room for “The Corrections” at some point in 2013.

HBO wouldn’t greenlight a series just to fill space on the calendar, of course, yet it's fascinating to wonder if Spike Lee's pilot "Da Brick," which was recently passed over as a possible series, would have had a better chance to be greenlit if the "Luck" decision was made before the "Da Brick" decision was made.

As for "The Corrections," HBO will naturally need to be satisfied with the creative aspects of the project before giving it a series order, but the loss of “Luck” may ultimately accelerate the pipeline at a network that has rarely had to rush shows into production.

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