Pat Mullen out at Fox Chicago duopoly, Renda in

Another GM shake-up at Fox-owned WFLD-TV and WPWR-TV has led Pat Mullen out the door after three rather unproductive years at the duopoly, and was replaced by Michael Renda of sister station WTXF-TV in Philadelphia, which is also a Fox O&O.

In turn, Patrick Paolini takes over the WTXF job after his stint as vice president and director of sales at WNYW and WWOR, Fox’s O&O duopoly in New York.

Under Renda’s watch, WTXF launched a successful 5 p.m. newscast where it finished first among adults 18-49 and adults 25-54 during May, ending the decades-long dominance of ABC-owned powerhouse WPVI-TV in the time period. (WPVI still won in households.)

But this is going to be more challenging: Renda will be running a station which is generally considered the weakest in the Fox O&O chain in a market which is home to one of the highest-rated ABC affiliates in the country.

As for the departing Mullen, he came to WFLD in April 2006 from Tribune (where he was head of the company’s station group), replacing Debbie Carpenter as GM. During his tenure, he expanded WFLD’s newscasts to 9 a.m. and 10 p.m., with disappointing results. News personalities Walter Jacobson, Mark Suppelsa, and Mike Barz departed the station in controversy, while ratings for the newscasts have not improved. The station’s 10 p.m. newscast was recently canceled.

Currently, WFLD does not plan to launch a 5 p.m. newscast – given WGNTV’s ratings for its local newscast at 5:30 p.m. (which also have been disappointing), but WGN is sticking with it for the long-term in the hope of ratings improving.

Meanwhile, ratings for WFLD’s syndicated programming – notably aging reruns of The Simpsons and Seinfeld have declined due to tougher off-network sitcom competition from WGN and WCIU, though TMZ is somewhat of a ratings hit. WPWR has been a disaster, with ratings for most of its shows hovering around a 1 while Everybody Loves Raymond – which it lured from WGN back in March 2008 – has not lived up to expectations.

Another of WPWR’s somewhat reliable ratings performers (The Tyra Banks Show) is leaving for a daytime slot on CW beginning next week. First-run shows on the station – notably Temptation and Trivial Pursuit – have bombed and were not awarded second seasons. Other programs (like Jerry Springer and Cops) have clearly overstayed their welcome.

But the good news for WFLD and WPWR is the arrival of some new highly anticipated programs to the duopoly this fall. Reruns of NBC’s demo hit The Office begins airing on WFLD weeknights beginning Sept. 21 at 6:30 P.M. and 10 p.m, while My Name is Earl reruns are expected to land on sister station WPWR.

Dr. Oz, a new talk show from Oprah Winfrey’s Harpo Productions and Sony Pictures Entertainment, takes the 10 a.m. and 4 p.m. time slots on WFLD beginning Sept. 14, while The Wendy Williams Show (which premiered July 13) owns the 3 p.m. and 12:05 a.m. time slot on the same station. Wendy Williams has done well in several key demos at 3 p.m. (in women 18-34 and women 18-49.) thus far.