He spent his college career at Kansas State University and is one of the top all-time scoring leaders at the school. His first three seasons he was coached by Jim Wooldridge and his senior year he was coached by Bob Huggins.
After his senior season, he entered the 2007 NBA Draft but went undrafted. In his first professional year, he went overseas to play for the Turkish Basketball League's Antalya Büyükşehir Belediyesi. After one season in Europe, he was selected in the first round (15th pick overall) of the 2008 NBA Development League Draft by the Iowa Energy.
On January 29, 2009, he was signed to a 10-day contract by the Charlotte Bobcats,  having averaged 20.6 points per game in 21 games with the Iowa Energy. He was named to the 2009 D-League All-Star Game, although he did not compete owing to his status with the Bobcats.
He was signed by the Bobcats to a second 10-day contract on February 8, and then signed for the rest of the season on February 18, 2009. 
On January 10, 2010, Martin was signed to a 10-day contract by the Golden State Warriors.  After his second 10-day expired, he returned to the Iowa Energy of the NBA D-League.  On March 30, Martin signed a 10-day contract with the Washington Wizards.  On April 9, he signed with the Wizards for the rest of their season. 
In August 2010, Martin was invited by the Wizards to their training camp for the 2010–11 season.  On April 6, 2011, he was waived by the Wizards.  On July 10, he signed with Jilin Northeast Tigers of the Chinese Basketball Association. 
On July 12, 2012, Martin re-signed with the Wizards. 
On October 15, 2013, he signed with the Atlanta Hawks.  On January 7, 2014, he was waived by the Hawks. In 25 games, he averaged 6.6 points per game.  On January 10, he signed a 10-day contract with the Chicago Bulls.  On January 20, he signed a second 10-day contract with the Bulls.  He was subsequently not signed for the rest of season after his second 10-day contract expired.  On February 1, Martin signed a 10-day contract with the Atlanta Hawks.  On February 11, he signed a second 10-day contract with the Hawks.  On February 21, he signed with the Hawks for the rest of the season. 
On August 18, 2014, Martin signed with the Detroit Pistons.  In 23 games during the 2014–15 season with Detroit, Martin averaged 1.6 points, 0.9 rebounds and 0.5 assists in 8.6 minutes per game.  On June 1, 2015, he exercised his player option for the 2015–16 season with the Pistons worth $1.27 million.   On October 23, 2015, he was waived by the Pistons.   On October 31, he was selected by the Iowa Energy with the fourth overall pick in the 2015 NBA Development League draft.  On January 12, 2016, he was waived by Iowa. 
NBA career statistics
|GP||Games played||GS||Games started||MPG||Minutes per game|
|FG%||Field goal percentage||3P%||3-point field goal percentage||FT%||Free throw percentage|
|RPG||Rebounds per game||APG||Assists per game||SPG||Steals per game|
|BPG||Blocks per game||PPG||Points per game||Bold||Career high|