The long-awaited football series between the Texas A&M Aggies and Oregon Ducks is off.

Aggies athletic director Eric Hyman exercised a clause in the series contract that could void the agreement if the Aggies switched conferences, FOX Sports reported Thursday, and Texas A&M moved from the Big 12 to SEC in 2012.

Craig Pintens, Oregon senior associate athletic director for communications and marketing, confirmed Thursday afternoon that Texas A&M withdrew from the series via its change-of-conference clause.

"We are disappointed in Texas A&M's decision," Oregon athletic director Rob Mullens said in a statement. "We want to continue to provide marquee non-conference matchups for our fans. Scheduling is very difficult and when a team cancels a game we need to work even harder to find a suitable replacement."

The series was scheduled in 2009 as a top non-conference opponent for each school but with the Ducks' continued success, combined with A&M's rise in popularity behind coach Kevin Sumlin and Heisman Trophy winning quarterback Johnny Manziel -- a former Oregon recruit -- the series grew to marquee status.

One of the architects of the series was then-A&M athletic director Bill Byrne, who was also Oregon's athletic director from 1982-92.

It isn't the first time the Aggies have backed out of a series with a premier Pac-12 opponent. In 2013, one year after he took over as AD in College Station, Hyman opted out of a 2015-16 series with USC -- a deal that also had been reached in 2009 -- citing the uncertainty of switching to the SEC.

With the Aggies off the schedule, the Ducks' only non-conference opponent on the books for 2018 is Bowling Green, with Nevada in 2019, per fbschedules.com.

The Ducks retain high-profile home-and-home matchups with Nebraska (2016 and 2017) and Ohio State (2020 and 2021).

-- Andrew Greif | @andrewgreif

Oregonian reporter Tyson Alger contributed to this report.