NBA career New Jersey Nets (2006–2008) Williams was selected 22nd overall in the
2006 NBA draft by the
New Jersey Nets, using the pick they got from the Denver Nuggets in a trade for
Kenyon Martin. Former teammates
Josh Boone,
Rudy Gay,
Hilton Armstrong, and
Denham Brown were also selected, with all but Brown being first-round picks. Marcus Williams was named to the Rookie team for the 2007
T-Mobile Rookie Challenge at the
2007 NBA All-Star Weekend. As a rookie in 2006–07, Williams played in 79 games, averaging 6.8 ppg and 3.3 apg.
Golden State Warriors (2008–2009) On July 22, 2008, Marcus Williams was traded by the Nets to the
Golden State Warriors for a conditional first-round pick. On March 10, 2009, he was released by the team.
Memphis Grizzlies (2009–2010) In July 2009, Williams began playing on the
Memphis Grizzlies Summer League team in Las Vegas, Nevada. He joined
2009 first-round pick
Hasheem Thabeet, undrafted rookie free agent
Jeff Adrien, and
Rudy Gay as one of four former
UConn Huskies on the Grizzlies' Summer League roster. On August 7, 2009, Williams officially signed with the
Grizzlies.
International career Piratas de Quebradillas (2009) in 2010 against
Estudiantes in 2013 Williams signed with
Piratas de Quebradillas of the
Puerto Rican Basketball League (BSN) in late March 2009. During the first half of the season, Williams averaged 15.0 points per game, 5.3 rebounds and 9.3 assists. He had registered one triple-double and was the league-leader in assists. He was also selected to play in the league's All-Star game and won the game's MVP award, as well as winning the Skills Contest. He also finished the season earning All-BSN First Team honors with teammate
Peter John Ramos, and helping the Pirates to the best record in the league. Because he went to the
Memphis Grizzlies' summer league team and left the Pirates, he missed the league finals, and the Pirates lost the championship.
Enisey Krasnoyark (2010–2011) In August 2010, Williams signed a one-year contract with the Russian team
Enisey Krasnoyarsk. Quickly becoming leader of his new team, Williams helped Enisey qualify to playoff for the first time in club's history. In quarterfinals Enisey lost series to Lokomotiv-Kuban (1:2). Williams was named "Player of the Month" in Russian PBL League in November and December. He was also selected All-Star 2nd team. Williams finished season with 14.8 points per game and as league's best in total assists (184) and assist per game (6.8).
Jiangsu Dragons (2011–2012) In late November 2011, Williams signed a contract with the
Jiangsu Dragons of China. In 25 games, he averaged 11.1 points, 3.2 rebounds, 3.8 assists and 1.2 steals in 25.8 minutes.
Unicaja Málaga (2012–2013) In 2012, Williams signed a one-year contract with the Spanish team
Unicaja Málaga. In 53 games, he averaged 9.6 points, 2.6 rebounds and 3.3 assists in 22.2 minutes. In 47 games, he averaged 9 points, 2.6 rebounds and 4.2 assists in 25.6 minutes. On November 22, 2014, in a game against
Galatasaray, Williams set a Euroleague record for the most assists in a single game (17). He also added 8 points while shooting just 3–16 from the field. However, his team lost after double overtime with 110–103. With Crvena zvezda, he won the
Adriatic League championship, the
Serbian League championship and the
Radivoj Korać Cup. On November 3, 2015, he re-signed with Crvena zvezda, but on December 28, 2015, he and the team parted ways.
Budućnost Podgorica (2016–2017) On July 27, 2016, Williams signed with Montenegrin club
Budućnost Podgorica for the 2016–17 season. On March 26, 2017, he was released by Budućnost. In 27 league games, he averaged 10.3 points, 2.5 rebounds and 6.1 assists in 25.4 minutes, while averaging 12.3 points, 1.3 rebounds, 5.1 assists and 27. minutes in 7 Eurocup games. In 9 games, he averaged, 8.3 points, 2 rebounds and 3.4 assists in 23.1 minutes. On October 10, 2017, he was waived by the Kings after appearing in two pre-season games. On October 21, he signed with the
Reno Bighorns, where he averaged 10.8 points, 2.9 rebounds, 6.5 assists and 26.6 minutes in 49 games.
Stockton Kings (2018–2019) For the 2018–19 season, Williams re-joined the G League with the
Stockton Kings. On February 5, 2019, Williams was suspended for five games without pay for violating the terms of the league's anti-drug program. ==Career statistics ==