A month before champagne was spraying in the Mets clubhouse, there was something with a far fouler scent permeating their Triple-A team’s home.

The Las Vegas 51s have come under criticism for the poor condition of their stadium — Cashman Field — after the clubhouse was flooded with feces during an Aug. 22 game. The Las Vegas Review Journal obtained two admonishing letters from Pacific Coast League commissioner Branch Rickey III to the Las Vegas Convention and Visitors Authority, which is the park’s landlord.

“That particular problem is representative of what are more regular and pervasive infrastructure issues,” Rickey wrote, according to the paper.

“The salient point is that the Cashman facility has deteriorated. To assure it will be ready for play beyond 2017 and 2018 might force an expenditure of many tens of millions of dollars and still not provide an optical long-term solution.”

The league is essentially pushing for a new stadium to replace the 33-year-old home of the Mets’ top minor-league team. He also noted it was troubling how teams closer to Las Vegas, such as the San Diego Padres and Los Angeles Dodgers, have opted to put their minor league franchises “in far less appropriate markets.”

The Review Journal said LVCVA president Rossi Ralenkotter, speaking at a board meeting, was noncommital as to whether he would be interested in building a new stadium. The paper noted he sounded more interested in short-term fixes for the out-of-date stadium, whose problems go beyond the sewage system.

“Maintaining a viable franchise here in the face of such adversity is difficult already and soon will accelerate into unsustainable,” Rickey wrote.

The Mets signed a two-year extension in 2014 that keeps their far-flung affiliate in Sin City through next season.