"We'd like to play with everything open, but we don't know," Marlins president David Samson said of what the team preferred for the opener.
Samson said during previous batting practices, there seemed to be a jetstream when the roof is opened and the windows are closed.
The roof is expected to be closed for roughly 70 of Miami's 81 home games this year. But winds and rains also will factor into the decisions.
It takes about 12-14 minutes, depending on wind conditions, for the roof to open and shut.
The Marlins on Monday night kept the roof closed during warm-ups against the Yankees. But at about 6:50 p.m. ET, the roof and the operable wall in left opened on a comfortable South Florida night.
The decision on the roof for Wednesday's opener against the Cardinals will be made at 3:30 p.m. that day.
Playing two exhibition games with the Yankees allows the Marlins to get a feel for how the ballpark will work in terms of traffic flow, parking, concession stands and the game itself.
On Sunday afternoon, there were a few hiccups that were addressed.
"A lot of people found a lot of ancillary spots, which is great," Samson said of the parking situation. "All of those extra spots that are available, that's starting to work itself out. We had a small leak in the roof track in section 320, which was from the valve not being closed. The valve is now closed, so that will not happen again."
Samson said the team is getting plenty of feedback from fans about the park.
"It's all major, because you don't want anyone to complain about anything," Samson said. "We take them all seriously. We answer all e-mails. We take people's suggestions."