The hardest working cops in the LAPD are on the verge of getting the official call for a fifth season of TNT’s “Southland.”

TNT would not comment but negotiations are nearing an end and a deal is expected to close this week. Sticking point seems to be on how many episodes will be ordered: Warner Bros. TV and exec producers John Wells, Christopher Chulack and Jonathan Lisco are looking for 13 episodes while the network has offered 10, as the show has done for its past two seasons.

Season four closed out in March with a ratings uptick from the previous year, with 2.9 million viewers tuning in each week. In the 18-49 demo, “Southland” averaged 1.3 million viewers and 1.4 million in 25-54. Both those numbers were slight increases from a year ago though total viewers were off 2% from 2011.

Also, the medium age for the “Southland” audience fell to 48, two years younger than the audience for last season.

Ensemble cast includes Michael Cudlitz, Ben McKenzie, Shawn Hatosy and Regina King. Lucy Liu was a guest star for all of last season but is not expected to return.

“Southland” bowed as a midseason entry on NBC three years ago, filling the 10 p.m. Thursday slot that had been occupied for years by the Wells-produced “ER.” NBC wound up canceling the series as it prepped for the short-lived run of “The Jay Leno Show” as a 10 p.m. weeknight strip. TNT quickly picked up the property, and since then “Southland” has ranked as the cabler’s most critically embraced series.