Last week it was revealed that the former first-round pick had been away from organized team activities after medical tests regarding a heart condition put his status in question.
On Thursday, Saints coach Sean Payton told reporters that Fairley's evaluation is "still ongoing" and that the team is waiting to see what the final outcome will be.
"He's gotten two professional opinions, Payton said. "The first one was one that advised that he shouldn't play football again. The second opinion was a little different, and he's getting a third opinion or he's already gotten a third opinion, we're waiting on that opinion.
"The things we know are this, it's obviously something significant and serious that we've got to pay attention to, obviously both for Nick and for the club. So we're hopeful and yet we're guarded because of the type of condition that we're talking about."
Fairley, the No. 13 overall pick in 2011 by the Detroit Lions, has played six years in the NFL with the condition.
The Saints signed Fairley to a four-year, $28 million contract this offseason, which contained $14 million in guarantees.
NFL Network's Mike Garafolo reported Thursday the Saints have paid half of Fairley's $8 million signing bonus, and are hoping for more "clarity" about his condition before paying out the other half, which is due June 15.
"If it's an illness that wasn't previously disclosed, the team can then say 'this is a non-football injury -- we don't owe you anything' and can take back all of the money," Garafolo said on NFL Network's Inside Minicamp Live. "But in this case, he had this before. Teams have known about this going all the way back to the [scouting] combine in 2011. So any kind of attempt to take all of the money, that might get a little bit hairy there. The third opinion that they are waiting for, I am told that this is coming in the very near future. So look for a little more clarity to come here in the coming days"
Now Fairley's future appears to be in the doctors' hands.