Fox Networks is considering hiring an outsider to run its advertising sales, a signal of the importance executives at the 21st Century Fox unit have placed on the position.

Fox Networks has been without a formal ad-sales chief since September, when Toby Byrne, who led ad-sales efforts at Fox Broadcasting, Fox Sports and other parts of the unit, stepped down. Since that time, Randy Freer, Fox Networks’ chief operating officer, has led the company’s Madison Avenue outreach, aided by Bruce Lefkowitz, executive vice president of ad sales; Danielle Maged, executive vice president of global partnerships; and Joe Marchese, president of advance adverting products. Fox Networks also encompasses such operations as FX and the company’s international networks.

Should the company hire an executive from the outside, Fox would buck what has been the norm in recent months. At a time when many media companies’ ad-sales veterans are leaving, NBCUniversal, Discovery Communications, Viacom and AMC Networks have all found successors from within their ranks. Disney’s ABC in March will face a similar situation, when its ad sales president, Geri Wang, retires from the role.

Fox has tapped MediaLink, a media-industry consultancy run by Michael Kassan, to search for potential successors to Byrne, according to five people with knowledge of the situation. One of the candidates has been Adam Bain, the former chief operating officer of Twitter,  three of these people said. At present, Bain is not expected to take the job.

Fox Networks declined to make executives available for comment.

Fox has found success in the past by luring someone who wasn’t homegrown. In 1989, executives at the fledgling Fox Broadcasting wooed Jon Nesvig, a senior ad sales executive at NBC, to oversee relationships with Madison Avenue when the Fox was airing just two nights a week. Nesvig served as sort of adult in the room, so to speak, as younger executives tried to transform Rupert Murdoch’s seemingly quixotic notion of launching a fourth broadcast network into reality. Nesvig would grow to wield much authority at Fox and become a consigliere of sorts to Murdoch, now the executive chairman of the parent company.

The industry has changed since that time. Selling TV ads has grown significantly more challenging. The jobs now encompass broadcast, cable and digital, as advertisers seek what is known as “cross platform” approaches so they can woo an audience that is splintered across linear TV and on-demand streaming. A rising generation of viewers haa grown accustomed to ignoring ads or seeing fewer of them.

“The future is ad-light or ad-free, making the job of an ad salesperson fundamentally challenging,” said Richard Greenfield, a media-industry analyst with BTIG.

Fox has made moves to shift with the times. The company has placed more emphasis on digital viewership, purchasing ad-tech company TrueX in December of 2014. Its leader, Marchese, has articulated a  strategy of creating ads that reward broadband users for their attention, letting them see special content or giving them a particular offer or benefit in exchange for watching a commercial.  Marchese is said to be a possible internal candidate for the larger ad-sales role, according to people familiar with the situation.

Fox has also worked to develop offers that help embed advertisers in programs. In July, Fox Broadcasting hired Laura Carracioli, a veteran executive with a long history of working to lace advertisers’ products and messages into content. Fox last season won notice for embedding Pepsi into a three-episode plot arc in “Empire.”