Owner Jeffrey Loria has been publicly shopping the Marlins since February but hasn't found a buyer.
''I think he's holding out for dollars right now that are unrealistic, is what I would guess,'' Ross said Thursday. ''They have their issues, certainly. But that's their problem. I've got to worry about mine.''
Three investment groups are now pursuing a purchase, and earlier this month baseball Commissioner Rob Manfred said all have offered about the same amount of money. Loria is believed to be seeking about $1.2 billion after buying the team for $158.5 million in 2002 from John Henry.
One investment group includes former Florida Gov. Jeb Bush and Quogue Capital investment fund founder Wayne Rothbaum. A second group is led by former New York Yankees shortstop Derek Jeter, and the third group is led by South Florida businessman Jorge Mas.
When Ross was asked if any of the groups approached him about joining them, he said, ''I've had phone calls, but I'm not interested. ... I have my hands full with the Dolphins and our stadium.''
Marlins President David Samson declined to respond to Ross' comments. The Marlins are expected to lose more than $50 million this year and are likely to miss the playoffs for the 14th season in a row, the longest drought in the National League.
Regarding another sport, Ross remains interested in moving the Miami Open tennis tournament to the Dolphins' stadium complex. Ross is willing to invest in a tennis center on stadium grounds because he wants to keep the event in South Florida.
''Stay tuned,'' he said of the plan. ''It's a thought.''
The tournament has been held since 1987 on the island of Key Biscayne near downtown Miami. The event's future has been in question since a 2015 appeals court decision that prevents upgrades to that complex.
On the first day of Dolphins training camp, Ross also addressed this week's report on 202 former football players whose brains were examined in a study finding evidence of debilitating disease in nearly all of them.
''We're all concerned about it,'' Ross said. ''There's a tremendous amount of research going into it and doing things to make it better.''
He also said: ''If I had a son, I'd have him playing football today.''
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