Undoubtedly the National Football League is king, but a Dallas Cowboys legend thinks trouble may be coming.

Hall of Famer Troy Aikman, the lead analyst on the NFL on Fox, told a Los Angeles forum last Friday he feels the wildly popular sport may be in jeopardy.

"The long-term viability, to me anyway, is somewhat in question as far as what this game is going to look like 20 years from now," Aikman said.

The Super Bowl XXVII MVP said the NFL Network's struggles should be a red flag to owners: "People couldn't get [the channel] in the homes and, all of sudden, fans, me included, were saying, 'I wasn't getting the Thursday night game and I was OK with that.' That’s not a good thing."

Aikman spoke of his worry about the dilution of a product that is currently wildly popular.

"At one time, watching football was an event," Aikman said. "'Monday Night Football' was a big event. Now you get football Sunday, you get it Monday, you get it Thursday and, late in the year, you get it on Saturday."

Aikman did not mention which sport might end up passing football in popularity.

"I think we’re going to look back at this point in time and say these were the missteps that the National Football League took that kept football from being the No. 1 sport," Aikman said, as reported by the Los Angeles Times. "I believe, and this is my opinion, that at some point football is not going to be the number one sport. You talk about the ebbs and flows of what’s popular and what’s not. At some point, the TV ratings are not going to be there. I can’t justify that because the numbers say otherwise (now), but I guess time will tell."

Aikman debuted with the Cowboys in 1989, playing until 2000 in a career that included six Pro Bowls and three Super Bowl championships alongside Emmitt Smith and Michael Irvin. The former UCLA quarterback passed for 32,942 yards and 165 touchdowns during his pro career. He ended up the winningest starting quarterback of any decade with 90 of 94 career wins occurring in 1990s.

The Cowboys great also mentioned his concern about concussions, and whether anything can be done to remedy a situation that doesn't seem to be getting any better with increased research.

Aikman said if he had a son, "I don’t know if I would be encouraging him to play."

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