MADISON, Wisc. -- In late December, the Big Ten and Pac-12 announced that they would enter into a new scheduling partnership, and that by 2017 there would be an annual football series involving all 12 schools in both leagues.

But Wisconsin athletic director Barry Alvarez told ESPN.com on Thursday that the partnership in football had not been finalized because "there are a couple of teams in the Pac-12 that are dragging their feet a little bit."

"We hope we can finalize it," Alvarez said. "I think it would be healthy for our league and their league."

The sticking point, Alvarez said, is how difficult the schedule could become for some Pac-12 teams. That league is committed to playing a full nine-game conference schedule. A Big Ten opponent would mean 10 tough games, and schools like USC and Stanford have an annual series with Notre Dame.

"So I can see why somebody would be reluctant to jump in with both feet and say, 'Hey this is great,' with the schedule they're playing," Alvarez said. "Most of the people I've talked to have been in favor it, and the ADs out there have been in favor of it. But I can see where some people, some coaches could be reluctant."

However, when contacted by ESPN.com, the Big Ten said the series is still on. The league issued this statement from commissioner Jim Delany.

"We have just concluded very high level presidential meetings, at which time both conferences reaffirmed plans to play an annual 12 inter-conference game football schedule beginning in 2017, subject to previously contracted non-conference games. It was also reaffirmed that the collaboration was critically important to implement across a wide area of athletic and academic endeavors. We have made significant progress across the board in other scheduling areas."

Alvarez said the series will be discussed further when Big Ten athletic directors meet next month in Chicago. While it appears to still be a go, this is a reminder that 2017 is a long way away, and conferences' priorities can change. Remember when the Big Ten was seemingly gung ho about a nine-game league schedule?