MIAMI -- When players get their first big-league hit or first Major League homer, they try to get the ball as a souvenir. Adam Greenberg wanted his batting helmet from Saturday's game.

The first Major League pitch Greenberg saw in his first big-league at-bat struck him in the back of the head, and knocked him out of the game. Florida's Valerio De Los Santos threw the fastball in the ninth inning of the Chicago Cubs' game at Dolphins Stadium.

Greenberg, 24, called up from Double-A West Tenn for Friday's game, fell to the ground clutching the back of his head.

"When you see it now, you think, 'Could I have gotten out of the way?' But it happened so fast," Greenberg said. "I get in the box, and all of a sudden he throws it, and I'm thinking, 'Am I swinging?' And all of a sudden, bam.

"I've never been more scared in my life," he said. "I thought my head was split open, I really did."

He remembers the entire sequence of events, including Marlins catcher Paul Lo Duca standing over him and telling him to be still.

"I knew what was going on, I never lost consciousness," Greenberg said. "I know everything [Lo Duca] said. I saw him and the umpire, and then Mark [O'Neal, Cubs athletic trainer] and Dusty [Baker, Cubs manager] came over."

Greenberg's family had made the trip from Connecticut to see their son in a big-league game for the first time. His mother is a nurse, and used to work in the operating room, so she stayed with her son all night Saturday. The medical staff wanted Greenberg to be awakened every couple hours. Cubs pitcher Kerry Wood had volunteered to monitor the kid, not knowing his parents were in town.

Greenberg went to a local hospital on Sunday for a CT scan. He still had a headache and was a little woozy, which O'Neal said was standard for anyone suffering a mild concussion.

"His symptoms are very minor, but he came in with some mild dizziness and headaches, and we just needed to make sure," O'Neal said.

The outfielder should be able to play after the All-Star break.

"The concern is getting hit again," O'Neal said. "He needs to be completely symptom-free, no headaches, no dizziness. You want to make sure all of his senses are back to normal before you put him back out there."

Cubs team physician Dr. Stephen Adams was a little miffed at Greenberg. The Cubs were a little shorthanded at that point in the game, and pitcher Carlos Zambrano was called on to pinch-run for Greenberg. It was good-natured kidding.

De Los Santos called the Cubs clubhouse after Saturday's game to talk to the young outfielder. Greenberg was touched.

"I've never been more scared in my life. I thought my head was split open, I really did."

-- Adam Greenberg

"I've never heard anyone more distraught," Greenberg said of De Los Santos. "He was very genuine, very sincere. No one [throws at someone's head] intentionally. Whatever the circumstances, pitches get away. It's unfortunate. He said he wasn't even ready to pitch after that. The sincerity in his voice, I could tell he was sorry."

Greenberg will fly home to Connecticut with his family on Sunday, and then go to Chicago on Wednesday. He can't wait to get back in the batter's box again.

"Absolutely -- although not today," he said. "Seeing straight is hard enough, let alone seeing a ball coming at you. The All-Star break couldn't happen at a better time. It'll give me a couple days to just relax. I'm ready to get back in there."

He does have a welt on the back of his head.

"They told me I'd be a little dizzy, a little groggy, but it's nothing to be concerned about," he said. "The bottom line is we came back and won the game. It makes it a lot better."

His helmet doesn't have much of a dent in the back, but he wanted to make sure and save it.

"If you're going to get hit in the head, you'd rather be in the big leagues than anywhere else in the world," he said. "I know this is something I'll never forget."