Five more days.

Negotiators for the NFL and the players’ union begin five days and nights — at least — of talks toward reaching a new collective bargaining agreement on Monday. Failure by the time Friday ends could mean the first pro football work stoppage since 1987.

Enough progress was made in 11 days of meetings overseen by federal mediator George Cohen that two extensions to the current CBA were granted: first for 24 hours, then for seven days. That doesn’t mean the owners and players association are on the verge of any major breakthroughs.

But, unlike in the previous months when there was little movement — except in opposite directions — the two reprieves last week were encouraging.

“I think what the mediators bring to the process is a structure and a discipline that wasn’t always there,” said Jeff Pash, NFL executive vice president and chief negotiator. “They inject a seriousness of purpose to it. They encourage you. They keep you going.”

So they will keep going on such issues as how to split the $9 billion in revenues America’s most popular sport rakes in. And a potential 18-game regular season, a rookie wage scale, health benefits, and pensions.