Off-camera tension between media personalities who work together is hardly a new phenomenon. In one of the more famous examples, Mike Francesa and Chris Russo, who partnered on an immensely popular and polarizing show (Mike And The Mag Dog) on WFAN-AM Radio in New York from 1989 to 2008, went through multiple three-month stretches during which neither spoke to the other off the air. Away from sports, television morning shows have a long history of on-air love and off-camera animus, from Ann Curry and Matt Lauer on Today to Michael Strahan and Kelly Ripa on ABC’s Live, where friction first led to the end of their pairing and then to a string of tabloid covers.

ESPN Radio is now experiencing some off-camera issues of its own. Multiple ESPN staffers, including current and former employees who have had roles with the show, told SI.com last week that the once-warm relationship between partners Mike Greenberg and Mike Golic has turned icy over the last year, prompting a number of ESPNers to predict that the show will conclude long before this December’s contractual end. The sources said Greenberg and Golic are not talking to each other off the set—and hardly at all before the show or during commercial breaks.

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Through an ESPN spokesperson, both Greenberg and Golic declined comment.

“It’s really a poisonous atmosphere right now,” said one longtime ESPNer who has worked on the show. “Most of us don’t see the show lasting through its contractual end [which is believed to be the end of December]. But I give both these guys immense credit because when the light comes on, you would not know what’s going on. They are pros on air.”

“They are marvelous actors on set,” said another ESPN on-air staffer, who speaks to both Greenberg and Golic. “But they barely even make eye contact with each other these days.”

“They virtually ignore each other off air,” said a third ESPN staffer who has previously worked on the show and said such tension has existed since late last year.

What caused the chill between the two hosts, whose on-air partnership began in October 1998 and is one of the most successful sports radio pairings of alltime? A number of factors, according to those around the program. Last week, as reported by many outlets, members of the Golic family, particularly Mike’s youngest son, Jake, were not shy about making public their animus over how ESPN management has handled the show over the last 24 months.

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“Am I allowed to tweet that you guys are idiots now, or do I need a year to announce that,” tweeted Jake Golic, in a reference to ESPN management not making public what most inside ESPN have known for some time—that Greenberg is leaving Mike & Mike to host his own television show beginning Jan. 1, 2018. That show will originate from a studio in New York City and air live from 7 to 10 a.m. ET on ESPN, and re-air each day at 10 a.m. ET on ESPN2. Golic will continue on ESPN Radio with new partner Trey Wingo, who has experience on ESPN Radio and is one of the network’s signature NFL hosts. Mike Golic Jr. will also be part of the show each morning from 6:00 a.m. to 7:00 a.m. That show, still based in Bristol, Conn., is expected to simulcast on ESPNU. Most people I spoke with for this story predicted the Golic-Wingo pairing will start sometime in the fall.

Said an ESPN spokesperson on Monday afternoon: “Mike and Mike will continue into the fall.”

As for the background that led up to the current tension between the two co-hosts: at the ESPN annual upfront presentation for ad buyers in May 2015, the company boldly announced that Mike & Mike would move to New York City and begin broadcasting from ABC’s Times Square studio at 6 a.m. ET on Feb. 8, 2016, the day after Super Bowl XL. The move was designed to turn Mike & Mike into a Good Morning America-style program, including actual on-air interaction with the ABC morning show, which is also under the Disney aegis. At the time, Mike Golic called it a “nice second act for the show” and said he would be moving his family just outside New York City. Greenberg, who grew up in Manhattan, said he was excited to be closer to the city. The announcement remains on ESPN’s PR site.

That move, of course, never happened and it's hard to discern why, though multiple ESPNers said both were in contract negotiations that included the show move before ESPN ultimately pulled the plug on New York City. Cris Carter was later added to—in theory—give it more juice. Carter now works at Fox Sports and will compete against Greenberg in the mornings.

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In Sept. 2016 SI.com reported that ESPN executives were exploring moving Greenberg into a new role as the lead host of a new morning television show. Sources at ESPN say Golic had no idea that Greenberg was pursuing such an option and that he may have even learned of it via the SI.com article. “From Golic’s perspective, he thinks Mike [Greenberg] should have come to him and told him he wanted to do his own thing,” said one of the ESPN-ers. “But Greeney is very non-confrontational, truly a nice a guy, and he would say that it wasn’t incumbent on him to tell Golic everything about what he wanted to do professionally. I guess I can see both sides.”

In January SI.com reported that ESPN executives were moving forward with a plan to give Greenberg a solo show. Greenberg also changed agents last year—he previously shared an agent with Golic—and signed a big deal with ESPN, which ESPN book author James Andrew Miller reported to be $6.5 million annually. That’s well over what Golic would be making on a radio-centric deal.

At last week’s ESPN’s Upfront presentation, Greenberg said, “Over the years I have thought many times about wanting to do something different. Many times it was going out of sports. Over the course of my life I did think I would maybe go away from sports and going into news or something different. The right thing never came up. So to leave what I am doing, which has been so good, I mean, getting teamed up with Mike Golic is the best thing that ever happened to me professionally. To leave that, I would not have done it if I did not have the chance to do something really good. So I hope I do this as long as I continue working because I can shape this into whatever I want”

Last Wednesday, Golic, through body language that could be read by a first year psychology major, offered this take on the dissolution of the show.

Said Golic: “The last year and a half have been interesting if not eyebrow-raising, as well. For me, it’s not my story to tell. I’m going to continue doing this exact same show. It’s for others to tell who made this decision if they want to tell it and how they want to tell it. Not my story to tell… So, basically as Greeny said, this show will go on for a while. We don’t know how long into this year, and then as I start a new show with Trey Wingo—who I’ve known for years, I’ve done football with since 2003—and my son Mike, so how could I not be excited about that?”

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Greenberg on air called the show “the best thing that has happened to him in his professional life” but he did not elaborate on what led to the parting of ways. For fans of the show, there is one silver lining: As the show gets closer to its conclusion, it is likely that the thaw between the two hosts will, in some parts, turn to melancholy. They will both recognize (and likely publicly) how good a professional partnership it has been.

“It was very telling in that public statement that neither looked at each other,” said the ESPNer who has worked on the show. “I thought they would at least say, 'Hey, thanks for a great run.'”