"Adam played catch again on Monday of this week, and he experienced pain," Soloff said. "At this point, it seems like surgery is indicated."
Miller, who has had surgery on the finger once before, will meet with team physician Tom Graham on Monday in Baltimore, and barring anything unforeseen, Miller will have surgery Tuesday to repair tendons in the finger.
Still worse, there is a chance Miller could develop scar tissue and need additional surgery to remove it.
"Because the space is so limited, with a procedure of this caliber, there is a high incidence of secondary surgery to limit or remove scar tissue which would impede recovery of both range of motion and strength," said Soloff, who added that sometimes scar tissue doesn't develop for months after the original surgery. "There's no way of knowing when that would take place. It's just a complicating factor of the injury, of the surgery and of the subsequent rehab."
Even that, Soloff said, would not guarantee full recovery.
"The challenging thing of that is when you go in there a third time, you run the risk of further scar tissue development," Soloff said. "That's one of the reasons why it is such a challenging case."
Miller made the final decision after hitting a wall in his rehab.
"He gave it a valiant effort from a conservative standpoint," Soloff said. "As he increased intensity to face hitters in a game-like situation, he had increased symptoms. It is a surgery that he's given a great deal of thought to.
"It's something he feels as if he has to do to return to the high level that he is accustomed to."
Previously, Miller had surgery to close the gap on his middle finger, created by a lingering blister. He made six starts last season for Triple-A Buffalo before the surgery. A month ago, he again experienced soreness, and he could no longer bend the tip of his finger.
Tuesday's surgery will reconstruct the pulley system using a tendon from his wrist.
"It's a career-threatening injury," Soloff said. "We're hoping for the best."
Miller, who is 32-25 with a 3.51 ERA in 104 appearances in the Minors, was the 2006 EAS Pitcher of the Year for Double-A Akron.