Andersen was born in Long Beach, California, grew up in Iola, Texas, and played one year at Blinn College. Andersen began his professional career in the Chinese Basketball League and the American minor leagues. He then played in the NBA for the Denver Nuggets and the New Orleans Hornets. The 6 ft 10 in (2.08 m), 228 lb (103 kg; 16.3 st) center/power forward received a two-year ban from the NBA in 2006 for violating the league's drug policy, but was reinstated on March 4, 2008, and re-signed with the Hornets the next day. He returned to Denver later in 2008, and remained with them until 2012. He signed with the Heat in January 2013.
Andersen was born in Long Beach, California. He was the second of the three children of Danish corrections officer Claus Andersen and Linda Holubec, a Tennessee native who worked as a waitress at the Port Hueneme base, and played basketball in high school. In 1982, when Andersen was four, his family moved to Texas, using a loan from the Texas Veterans Land Board to purchase a 10-acre plot in unincorporated Iola, about 100 miles north of Houston. Shortly later, Claus left the family without even finishing the house they were building. The Andersens then lived off the land, with Linda working on low-end jobs and relying on the help of neighbors and Linda's brother, who was a Navy supply boat captain. During Andersen's middle school years, he and his siblings were even sent to a group home in Dallas for three years.
During high school, Andersen was convinced to take up basketball by the varsity basketball coach, who said the sport could give him a chance at a college scholarship. Andersen could not get the grades to attend the University of Houston, but went to Blinn College in Brenham, where the coach was the father of Andersen's high school coach. He played one season with the Blinn Buccaneers, leading the National Junior College Athletic Association players in blocks. He is the only Blinn student to ever play in the NBA.
Convinced that he could play professionally, Andersen dropped out of Blinn, not knowing he had to officially apply for the NBA Draft to get picked up. Andersen's high school coach arranged for him to play a series of exhibition games with the semi-professional Texas Ambassadors, and a game in China led Andersen to get an offer to join the Jiangsu Nangang Dragons of the Chinese Basketball Association. Late into the 1999-2000 season of the International Basketball League, Andersen joined the New Mexico Slam, averaging 1.6 ppg and 1.6 rpg in the final six regular season games. He also played in four playoff games. He remained in the IBL the next season on the Fargo-Moorhead Beez.
NBA Development League
Andersen was the first overall pick in the 2001 NBDL Draft, by the Fayetteville Patriots. He wound up playing just two games on the NBA D-League.
Andersen became the first D-League player called up by an NBA team, signing with the Denver Nuggets on November 21, 2001. He quickly became one of the top per-minute rebounders and shot-blockers in the league.During the 2002 Rocky Mountain Revue, teammates Junior Harrington and Kenny Satterfield nicknamed Andersen "Birdman" for his arm span and penchant for aerial acrobatics.
New Orleans Hornets (2004-06)
New Orleans Hornets (2004-06) In 2004, Andersen signed as a free agent with the New Orleans Hornets, and after his best statistical season — 7.7 points and 6.1 rebounds per game - got a four-year, $14 million contract. Andersen appeared in the NBA Slam Dunk Contest during NBA All-Star Weekend in 2004 and 2005, finishing 3rd and 4th (out of 4), respectively. In the 2005 contest, he unsuccessfully tried the same dunk eight times at the Pepsi Center.
Expulsion and reinstatement
On January 25, 2006, Andersen was disqualified from the NBA for violating the league's anti-drug policy by testing positive for a banned substance. Andersen's suspension fell under the league's category of "drugs of abuse," violation of which is possible grounds for expulsion from the NBA under the league's collective bargaining agreement. Andersen attempted to appeal the ruling through arbitration, but the arbitrator ruled to uphold his dismissal in March 2006. As Andersen waited for his reinstatement effective which could be given in January 2008, he was helped by a laywer friend in Denver, Mark Bryant, who became his adviser. Andersen spent a month in a rehab clinic in Malibu, and worked out and coached a boys' basketball team in Denver.
On March 4, 2008, the NBA Players Association granted Andersen's request to be reinstated as an NBA player.[ The reinstatement was effective immediately, and the rights to his services belonged to his former team, the New Orleans Hornets, who signed him to a contract on March 5, 2008.
Return to Denver
Following the 2007–08 NBA season, Andersen was released by the Hornets. Andersen signed with the Nuggets on July 24, 2008. The contract was worth $998,398 for one season. Andersen finished the season 2nd in the league in blocks per game at 2.42 per contest, despite only 20.5 minutes of playtime per game. His 5.68 blocks per 48 minutes played was the best in the NBA.
On July 8, 2009, Andersen and the Nuggets agreed on a five-year contract.
On July 17, 2012, the Nuggets waived Andersen via the amnesty clause. Nuggets General Manager Masai Ujiri, a friend of Andersen, reluctantly made the transaction in order to remove $9 million from the team's payroll cap to avoid the luxury tax.
Before he was waived by the Nuggets, Miami Heat head coach Erik Spoelstra had repeatedly lobbied Pat Riley to acquire Andersen.
On January 20, 2013, Andersen signed a 10 day contract with the Miami Heat. He was signed to a second 10-day contract on January 30, and signed for the remainder of the season on February 8, 2013. He was brought in as a backup center. LeBron James and Dwyane Wade cast Andersen in a starring role in the Heat's "Harlem Shake" video.
Andersen only played in 42 games during the season but still contributed to the Heat's success by putting up 4.9 points per game on 57.7 FG% and 4.1 rebounds in 14.9 minutes of play. After he joined the Heat, his team went on a 27-game winning streak, overall going 37-3 in regular-season games in which Andersen played. Andersen also gained legions of fans inspired by his head-to-toe tattoos, Mohawk haircut, and trademark hustle.
Andersen shot 15-15 in games 1-5 against the Indiana Pacers in the Eastern Conference Finals, including a 7-for-7 performance in game one that set a franchise playoff record, besting the 6-for-6 mark by Alonzo Mourning in 2007. Andersen was suspended in Game 6 of the 2013 Eastern Conference Finals without pay for committing a flagrant foul on Tyler Hansbrough.
At age 34, he reached the NBA Finals for the first time in his career. Against the San Antonio Spurs in the deciding Game 7 of the 2013 NBA Finals, Andersen recorded three points, four rebounds, and a block en route to his first NBA championship.
Andersen is known for brightly colored tattoos on his arms, chest, neck, back, hands and legs. His first tattoo was given as an eighteenth birthday gift by his mother, who has some body art of her own from her tenure in the Bandidos Motorcycle Club. Andersen's regular tattoo artist, Denver-based John Slaughter, estimates he has inked 75 percent of his body. He showed off those tattoos in PETA's "Ink Not Mink" ad campaign to protest the fur industry.
On May 10, 2012, Denver NBC affiliate 9News reported that Andersen's home was the target of an investigation of a suspected Internet criminal case by the Douglas County Sheriff's Office Internet Crimes Against Children Unit. Andersen was not charged with any crimes. His lawyer said that Andersen was the victim of an extortion attempt, and that the case "had nothing to do with children".
Andersen is fond of charity work, to which he donates most profits from exploiting his image - such a 2009 Arby's promotion in Denver that gave "Birdman" glasses. He and lawyer Mark Bryant want to launch the Freebird Foundation to help underprivileged children.