After graduating high school, Sykes committed to play college basketball for coach Brian Wardle and eventually alongside Marshall teammates Alfonzo McKinnie and Vincent Garret, at Green Bay. From his freshman year in 2011–12, Sykes was immediately inserted into the Phoenix starting lineup, and was also the youngest player in the nation, let alone youngest starter. He averaged 11.2 points and 3.3 assists per game. At the end of the season, Sykes was named to the Horizon League All-Newcomer team. As a sophomore, Sykes increased his production to 15.9 points and 4.3 assists per game and led the Phoenix to the 2013 CollegeInsider.com Postseason Tournament. He was named first team All-Horizon League. At the start of the 2013–14 season, Sykes was named to the preseason All-Horizon League team and was a nominee for the Bob Cousy Award for top point guard in the country. Sykes and 7'1" stand out player Alec Brown led the Phoenix to a 24–5 regular season record and finished first in the Horizon League. The season included an upset over eventual Atlantic Coast Conference regular season champion Virginia in a game which saw Sykes score 21 points and distribute 10 assists. In a 69–66 loss to Wisconsin, Sykes scored 32 points, including a highlight dunk in the first possession of the game. At the conclusion of the regular season, Sykes was again named first team all-conference, he was named an honorable mention AP All-American, and was named Horizon Player of the Year. A loss in the Horizon League Tournament, due in part to a Sykes injury, led the Phoenix to missing an automatic bid into the NCAA Tournament and playing in the National Invitation Tournament. For his senior season, Sykes had high expectations as he was placed on the Bob Cousy Award Watch List, the Wooden Award Watch List, and the Naismith Award Watch List during the preseason. On February 26, 2015, playing in his hometown of Chicago, Sykes scored a career-high 36 points against UIC to surpass the 2,000-point mark for his career. Sykes became the only active player in the nation with 2,000+ points, 500+ assists, and 400+ rebounds. He also became the only player in Horizon League history to record those same career totals. Sykes won the 2015 Horizon League player of the year to join the elite company of players to win the award twice. For the second time in his career, he was named to the Honorable Mention AP All-American team. For the week of January 4–10 of 2015, Sykes won the Naismith National Player of the Week Award. In that week, Sykes averaged 28.7 points, 5 rebounds, and 4 assists per game while shooting 53.6% from the field, 50% from three, and leading the Phoenix to a 3–0 record. Sykes set a conference record as he was named the Horizon League player of the week thirteen times over his career. Sykes was one of eight invitees to compete in the Slam Dunk Contest at the 2015 Final Four, where he placed second.
Professional career
Austin Spurs (2015–2016)
After going undrafted in the 2015 NBA draft, Sykes joined the Cleveland Cavaliers for the 2015 NBA Summer League. On September 28, 2015, he signed with the San Antonio Spurs, only to be waived by the team on October 21 after appearing in three preseason games. Nine days later, he was acquired by the Austin Spurs of the NBA Development League as an affiliate player of San Antonio. On November 13, Sykes made his professional debut in a 104–82 win over the Texas Legends, recording eight points, one rebound, six assists and three steals in 17 minutes off the bench. In his rookie season with Austin, including the playoffs, Sykes averaged 13.1 points, 3.3 assists, 3.6 rebounds, and 0.84 steals while shooting 45.9% from the field and 77.4% from the free throw line, and also recording a plus/minus of +196. Sykes elevated his play in the postseason, including a game in which he recorded 31 points and 6 steals in a 26-point comeback in a win-or-go-home game 3. Due to his success, he was invited to the 2016 NBA D-League Elite Camp.
Sykes signed with Scandone Avellino of the Italian Lega Basket Serie A on August 7, 2018. Sykes is featured in the 2018 documentary film Chi-Town, produced and directed by Nick Budabin. The film follows Sykes' path from high school to his brush with the NBA.
