Seven years after being struck on the back of his head with a pitch, the 31-year-old is getting another chance to step into the batter's box in a big league game.
"A dream come true, Part 2," Greenberg said on Thursday morning, summing up his emotions. "I think I'm more prepared emotionally for this, because of everything that has gone on the last seven years."
On NBC's "Today" show on Thursday, Marlins president David Samson announced to Greenberg that Miami planned to sign him to a one-day big league contract to play on Tuesday. Samson guaranteed Greenberg, 31, would get "one at-bat" at Marlins Park against the Mets.
"It doesn't matter if I get a hit or I don't, this has already been a success," Greenberg said.
Marlins manager Ozzie Guillen said he is considering starting Greenberg and giving him one full inning.
"I don't know yet. I might start him," Guillen said. "Start him in left field and lead off. If he hits a home run, he stays. If he's out, he's gone. I think that's the easiest way."
Under that scenario, Greenberg would get his at-bat in the bottom of the first inning and then be replaced.
"That's the easiest way," Guillen said. "If he needs one at-bat, and the game is on the line, if I'm going to pinch-hit him, then I put myself in a position where I don't care about winning the game. To me, what is more important is to win the game. I think the best idea is to lead him off, play him in the outfield and then take him out after one at-bat."
There are a number of twists to Greenberg's story, because the head injury occurred in Miami, at the Marlins' old ballpark, Sun Life Stadium.
The "Today" show retold Greenberg's story of how he was struck in the head with a pitch in his lone big league plate appearance; and of the challenges the 31-year-old has faced with vertigo and vision issues, which still plague him.
Debuting with the Cubs on July 9, 2005, Greenberg came to bat as a pinch-hitter in the ninth inning against the Florida Marlins. The only pitch Greenberg saw was a 92-mph fastball from Valerio de los Santos. It plunked the 5-foot-9, 180-pounder in the back of the head.
"Life is going to throw you curveballs or fastballs in the back of your head," Greenberg said. "I got hit by one of them. It knocked me down. I could have stayed there. I had a choice. I could have said, 'Poor me, and this is horrible.' But I chose to get up and get back in the box."
The message Greenberg hopes is delivered is one of persistence.
"Get back up," he said. "Keep going. If you do that, good things do happen. Sometimes it takes seven years. But you know what? Anything is possible. That just shows what is possible."
Carlos Zambrano, now with the Marlins, pinch-ran for Greenberg. Zambrano will again be his teammate on Tuesday.
There is another twist to the story. A couple of years ago, Greenberg faced de los Santos again in a Minor League game. The first pitch Greenberg saw was a cutter in on his hands for a strike. Greenberg ended up getting a hit in that at-bat. And the two talked afterwards, as de los Santos also was shaken for years by the incident.
"I'm extremely proud to extend this opportunity to Adam," Marlins owner Jeffrey Loria said in a statement. "He has earned this chance, as his love and passion for the game never diminished, despite his career tragically being cut short. I look forward to seeing Adam step up to the plate and realizing his comeback dream next Tuesday night."
As part of his agreement with Miami, Greenberg has agreed to donate his one-day salary to the Marlins Foundation, which will then make a donation to the Sports Legacy Institute -- an organization that advances the study, treatment and prevention of the effects of brain trauma in athletes and other at-risk groups.
Greenberg is a native of New Haven, Conn. He was drafted by the Cubs in 2001. Recently, he played for Israel in the World Baseball Classic qualifying round in Jupiter, Fla. He walked in his lone plate appearance.
"I'm mentally, physically as ready for this moment as I've ever been," said Greenberg, who thanked the Marlins repeatedly in his conference call. "I welcome it with open arms."
Greenberg's story has received national attention for years. What he hopes people understand is he isn't bypassing the system when so many others never get one big league break.
"This was never a gimmick," he said. "I got to the Major Leagues on my own merit, and I worked through the ranks as a little kid and all the way up. I earned that spot seven years ago.
"So the fact this is not just my first at-bat, I think that's important to know. It's not just, 'Oh, poor kid, let's just give him a shot.' I think that speaks a lot to the fact that I never did give up ... And I make that very clear, I'm no different or more special than anyone else. It just so happened that my story was Sunday Night Baseball on ESPN."
Matt Liston, a documentary film maker, has been pushing for Greenberg to get another opportunity. And a push was started for "One at Bat."
In MLB history, no player has ever had his big league career end on the first pitch, except Greenberg.
If the Marlins hadn't called, how much longer would Greenberg have pushed on in hopes of getting a chance?
"To say when I would have given up on the dream? It was starting to fade," he admitted. "Three years in independent baseball is tough. It's a tough road. But I couldn't be more blessed to have that campaign and what Matt did.
"It just show the power of the human spirit and what people can do, because they helped me. Everyone helped me kind of get myself back to this point. I keep saying, it's so much bigger than baseball."
In the record books, Greenberg's hit by pitch is considered a "plate appearance." He hopes to have an official at-bat.
The one-day contract the Marlins will sign Greenberg to will be the second-to-last game of the Marlins' season.
If Greenberg is used early in the game, chances are he will not be facing a 92-mph fastball. The Mets are scheduled to pitch R.A. Dickey, a strong National League Cy Young Award candidate who throws a 80-mph knuckleball.
"That's fitting," Greenberg said. "The story is not one that is kind of going on all the time. R.A. Dickey goes for his 20th win, and the knuckleball. Hey, I don't care. Somebody can underhand the ball. Somebody can throw it 120 or throw a knuckleball, it doesn't matter. I've said it already. It's already a success, no matter what happens in the box."
"I saw the documentary on him," Mets manager Terry Collins said. "Certainly it's a sad story, but I'm anxious to have a chance to wish him luck and tell him we all support his charge back to try to become a Major League player again. It's a sad case, but he obviously had some great skills because there's a lot of guys who didn't get one at-bat for lots of reasons. They might have gotten hit in the head in the Minor Leagues. Again, it's a sad case but I know our guys will be on the top step clapping for him when he gets in the batter's box."