Sources: A’s told they won’t be back at Triple-A Nashville

ST. PETERSBURG, Fla. — The A’s aren’t sure where their next Triple-A affiliate will be, but it will not be in Nashville. Instead, Oakland’s top affiliate next season is likely to end up neighbors with the Raiders.

The Nashville Sounds have informed the A’s that the affiliation agreement with the A’s is over, two sources told The Chronicle. One possibility to ink a deal with Nashville are the Rangers, who are expected to lose their Triple-A affiliate in Round Rock, Texas, to the Astros in the latest round of Pacific Coast League musical chairs. The Nationals potentially could be in the mix for Nashville, too, should Texas head to San Antonio instead.

The A’s are among the teams that have been linked to Las Vegas for next season, in large part because the Las Vegas 51s will play in a new stadium, and it’s long been known that the Mets will be moving their Triple-A affiliate from Las Vegas to Syracuse, N.Y.

Cashman Field, the longtime home of the 51s, formerly called the Stars, will be supplanted by the new Las Vegas Ballpark, a $150 million stadium in Summerlin, Nev. The A’s, starved for a new stadium themselves, enjoy having new Triple-A facilities: When former Triple-A affiliate Sacramento switched to the Giants after the 2014 season, the A’s reached a deal with the Sounds just as they were moving into brand-new First Tennessee Park.

The Las Vegas Review-Journal has called the A’s the favorites to wind up with Las Vegas, where the Raiders are slated to move in 2020. That appears even more likely with the Diamondbacks — the other major option — extending their Triple-A deal with Reno through 2020. The Brewers are another possibility. Whichever club doesn’t wind up with Las Vegas or San Antonio will wind up with Fresno, currently home to the Astros’ Triple-A club, as its top affiliate.

Affiliation agreements are typically reached before the end of September.

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Susan Slusser is a San Francisco Chronicle staff writer.