Right fielder Jeremy Hermida has a mild left hamstring strain, sustained on Saturday against the Orioles in Jupiter. Hermida, who is hitting in the cage, is confident he will be ready for the season opener.
Rabelo said he hopes to resume baseball activities this weekend.
"I'd like to be in their on Opening Day [lineup], but who knows?" Rabelo said. "Whenever I am back, I'm going to be going 100 percent. I want to be in uniform on Opening Day."
Complicating the catcher position is the fact that Treanor also is resting an injury.
The 32-year-old suffered cramping in his left calf muscle. He may be back in the lineup as early as Thursday.
On Tuesday morning, he was doing a series of running drills to test his leg.
"Our catchers, they're banged up," manager Fredi Gonzalez said. "Rabelo may be a little longer."
Rabelo had his whole left leg tangled up on the play at the plate with Kearns. Rabelo's left ankle grabbed and experienced a pull on his knee, and his hip also buckled.
The MRI results are to see if there is any damage to either the knee or hip. He says he is feeling a bit better right now, but will know more after consulting with the doctor on Tuesday afternoon.
Rabelo has appeared in nine spring games with 23 at-bats.
The Marlins acquired Rabelo from the Tigers as part of the Dontrelle Willis-Miguel Cabrera trade in December.
The Marlins plan on carrying two catchers, but they may have to reconsider if both are still suffering from aches and pains. Paul Hoover and John Baker, both projected to begin the season at Triple-A Albuquerque, may now be looked at as more serious possibilities to make the team.
Hermida, meanwhile, aggravated his left hamstring three days ago.
"It grabbed a little bit in there," said Hermida, who projects to bat third in the order. "I don't think it's too bad."
Hermida has had 36 at-bats, and on Tuesday morning, he was taking swings in the batting cage.
For now, he is getting treatment, and he's optimistic about having a quick recovery.
Asked if it would prevent him from being in the Opening Day lineup, he said: "I'd like to think not. I've made some strides these last few days, and I'm being positive about it."
With Hermida resting, the Marlins are getting a longer look at Brett Carroll in right field. Luis Gonzalez, better suited for left field, also has had some action in right field.