ST. PETERSBURG, Fla. -- The principal owner of the Rays says it's unrealistic for his team to play full time in the Tampa Bay area and a shared season with Montreal is the best option.

"I don't see it happening in St. Petersburg and would be hard-pressed to see it working in Tampa from what I know," Stu Sternberg said at a news conference Tuesday. "This is not a staged exit. This is about Tampa Bay keeping its hometown team and Montreal having one, too. I believe strongly in the sister-city concept. We're asking for open minds."

Commissioner Rob Manfred said last week the Rays have "broad permission to explore what's available." Tampa Bay is averaging 14,546 fans a game, lowest in the American League and well below the MLB average of 27,360. Only the Miami Marlins draw worse at 9,378.

"We are at or near the bottom in every economic category in Major League Baseball," Sternberg said in his remarks at the Dali Museum in St. Petersburg.

An agreement between the Rays and St. Petersburg for Tropicana Field runs through 2027. St. Petersburg's mayor has shot down the two-city possibility.

"The City of St. Petersburg will not participate in the funding of a new stadium for a part-time team," Mayor Rick Kriseman said. "We remain receptive to partnering with the Tampa Bay Rays to redevelop the Tropicana Field site and build a new stadium for a full-time team."

Sternberg envisions open-air stadiums in both cities but noted there are no plans to pay for them. He said an ideal target date would have everything in place for the 2024 season.

The Rays have played at Tropicana Field since their inception in 1998 and drew their lowest home crowd of 5,786 against Toronto last month.

Montreal has been without a big league team since the Expos left after the 2004 season for Washington and became the Nationals.

The Rays had looked into building a stadium for years, but in December abandoned a plan for one across the bay in Tampa's Ybor City area.

Private equity mogul Stephen Bronfman, whose father Charles was the original owner of the Expos, is part of a group spearheading the effort to return baseball to Montreal.

Sternberg said it's possible the Bronfman group could join the current Rays' ownership if the sister-city plans succeeds, but he will keep controlling interest.

Sternberg reiterated that the Rays will remain in St. Petersburg through 2027 but doesn't know what would happen after that if the plan fails.

A possible site for a new St. Petersburg ballpark would be Al Lang Stadium, a longtime spring training facility now used by a pro soccer team owned by the Rays.

Also under consideration: shifting the spring training season from Port Charlotte, Florida, to Tampa Bay to provide two more months of baseball in the area.