"I would have anticipated more progress, especially this year, than we have done," Boston said.
He also expressed concern about attendance and corporate support. Boston said New Mexico State is expected to narrowly meet the NCAA's two-year attendance minimum, averaging 15,000 fans per game, to maintain membership in the Football Bowls Subdivision.
"We need football to be successful here," Boston said.
Mumme, who formerly coached at Kentucky, Valdosta State and Southeastern Louisiana, signed a five-year deal that expires in January 2010. He was offered a one-year extension last December but did not sign it.
Boston said Mumme will receive a $385,000 buyout.
Mumme's arrival in Las Cruces four years ago coincided with New Mexico State's entry into the WAC. And while Mumme is respected for his wide-open "Air Raid" offense, his teams were just 4-28 in conference games.
New Mexico State hasn't reached the postseason since the 1960 Sun Bowl, currently the nation's longest skid without a bowl game.
Boston said the Aggies made strides under Mumme and the program has improved with better facilities.
"This team could have been 8-4 or 7-5," Boston said. "We were very, very competitive. The cupboard isn't bare. But at some point it is performance. You have to be able to win. You have to be able to sell the business side of it."
(This version CORRECTS SUBS 15th graf to correct buyout)
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