Albert Pujols has won an NL MVP award, a Gold Glove and a World Series. So it was no surprise that the high achiever scored a perfect 100 on his citizenship test.

The St. Louis Cardinals' star officially became a U.S. citizen Wednesday during a ceremony at the Eagleton Courthouse. Pujols' wife Deidre secretly arranged to have about two dozen relatives and friends watch U.S. District Judge E. Richard Webber swear in Pujols.

Chester Moyer, the officer in charge of the U.S. Citizen and Immigration Service office in St. Louis, said Thursday that Deidre Pujols served as her husband's tutor. Moyer said Pujols, 27, spent about a year preparing for the citizenship exam. That preparation showed on the exam.

"He even answered a bunch of additional questions and gave us more answers than we asked," Moyer said. "He clenched his fist and said, 'I got 100 percent!'

"He just had a grin from ear to ear," Moyer said. "He was thrilled to become a citizen."

Pujols' agent and officials with his foundation, the Pujols Family Foundation, did not return phone calls seeking comment.

The ceremony was open to the public, but there was no publicity about Pujols' participation. He was the only person sworn in on Wednesday.

Pujols grew up in the Dominican Republic and moved with his father to the Kansas City area when he was 16, graduating from Fort Osage High School in Independence, Mo., in 1998. He was selected by the Cardinals in the 13th round of the June 1999 free-agent draft after playing baseball at Maple Woods Community College in Kansas City.

In six major league seasons, Pujols has 250 homers, 758 RBIs and a lifetime .332 batting average. He was the 2005 MVP and has finished second three times, including last season when he hit 49 homers and drove in 137 runs while hitting .331 in leading the Cardinals to their first title in 24 years. The first baseman won his first NL Gold Glove in 2006.

Soon after the citizenship ceremony, Pujols flew to Florida to prepare for the opening of spring training. Pitchers and catchers report Wednesday and begin workouts the next day. Position players are due to report Feb. 19 and begin workouts Feb. 20.