VIERA, Fla. -- Shortstop Esmailyn Gonzalez, one of the best prospects in the Nationals organization, isn't who he says he is.

According to SI.com, which cited four sources, Gonzalez is actually a 23-year-old named Carlos Alvarez Daniel Lugo. The Nationals list him as being 19 years old.

Gonzalez's current agent, Stanley King, said early Wednesday morning he was shocked by the revelations.

"I hope this is a mistake," King said via telephone. "I was at his house this winter and he answered by his [baseball name]. I will look into this."

The Nationals agreed to terms with Gonzalez on July 2, 2006. The switch-hitting Gonzalez received a $1.4 million signing bonus, the largest the club has paid for an international signing.

At the time, the signing was considered significant for the Nationals because it demonstrated that they intended to compete with the Braves, Yankees and Red Sox for the best talent in Latin America.

In fact, team president Stan Kasten considered the Gonzalez signing the equivalent to the Braves signing outfielder Andruw Jones and shortstop Rafael Furcal in 1993 and 1996, respectively. Jones and Furcal became stars in the big leagues.

"This is an important signing," Kasten said at the time. "We can now compete for the best talent in Latin America. We will have a presence there."

According to SI.com, the negotiations were handled by Basilio Vizcaino, who helps prepare young players in hopes that they eventually sign big Major League deals and reward him with a percentage of a signing bonus.

Vizcaino is a close friend of Jose Rijo, the former big league pitcher and now a special assistant to general manager Jim Bowden, and Jose Baez, the Nationals' director of Dominican operations.

The signing had already raised red flags with the FBI and MLB's department of investigations, which are looking into allegations of improprieties regarding bonuses for Latin players.

As SI.com reported, it is not known if there is a real person or baseball player named Esmailyn Gonzalez, how the falsification of documents might have occurred, and if Gonzalez will be able to secure the proper visa to join the club at Spring Training.

This past season, Gonzalez played for the Gulf Coast Nationals and hit .342 with 33 RBIs and a .431 on-base percentage in 181 at-bats.

"Those are great numbers," a scout told SI.com. "But you should be hitting that well if you're that much older than your competition."

SI.com said that representatives from the Nationals plus Rijo and Vizcaino did not return calls requesting comment, and Kasten and MLB spokesman Pat Courtney declined to comment.

Rijo, who is in camp as a Spring Training pitching instructor, said no one from SI.com tried to contact him. He read the report on a reporter's BlackBerry. Rijo laughed and said that he knows the player as Esmailyn Gonzalez.

Rijo said he first saw Gonzalez a few year ago when the latter played in the Yankees' Dominican academy. Rijo didn't think there was anything suspicious about Gonzalez.

"I saw him for 2 1/2 years [before he signed with the Nationals]," Rijo said. "At that time, he wasn't older. I don't know what to believe anymore. I don't want to say any more. I don't want to jeopardize the investigation."

Asked how disappointed he would be if Gonzalez wasn't who he said he was, Rijo said, "In the Dominican, you never know anymore. It has been going on for so long."

Gonzalez is scheduled to report to the Nationals' complex on March 13 and participate in the full squad workouts two days later.