Youth and college Duka grew up in Montville, New Jersey, to an Albanian family originally from
Debar. Duka played at
Montville Township High School, won three New Jersey state titles and one national title at club level, spent time in the
Red Bull Academy, and played
college soccer at
Rutgers University. During his time at Rutgers, he led the team in scoring and was a 2008 All-
Big East selection. For his career, he played in thirty-six games, making thirty-five starts, scoring ten goals and contributing five assists. During his college years Duka played two seasons with the
Newark Ironbound Express in the
USL Premier Development League. He actually started 2008 with the
New Jersey Rangers but he never made an appearance for the club.
Professional Columbus Crew Duka was drafted in the first round (eighth overall) of the
2010 MLS SuperDraft by
Columbus Crew. He made his debut for the Crew on August 14, 2010, against
Real Salt Lake in a 2–0 defeat. Later that season he made his first start for Columbus, picking up a yellow card in a 1–0 victory at
D.C. United on September 4, 2010. Duka made five appearances in the
2010–11 CONCACAF Champions League, providing two assists, and also made three appearances in the
2010 Lamar Hunt U.S. Open Cup. Duka scored his first career goal on October 15, 2011, in a 3–0 victory over
New England Revolution. He trapped an attempted clearance outside the box and finished from the left side of the penalty area in the 59th minute. He would go on to score his second career goal in the Crew's next match, a 3–2 defeat to
Chicago Fire on October 22, 2011. Duka appeared against
Colorado Rapids in the
2011 MLS Cup Playoffs as the Crew were eliminated 1–0 by the defending champions in the wildcard round. Duka notched two assists from 20 appearances in
2012.
Chicago Fire After three seasons in Columbus, Duka was traded to
Chicago Fire on February 1, 2013, in exchange for
Dominic Oduro. Duka made his debut for the Fire on March 3, 2013, in a season-opening 4–0 loss to the
LA Galaxy. He was subbed off after 57 minutes. On June 22, 2013, in his return to Columbus, Duka scored in the 52nd minute of a 2–1 victory for the Fire, his first goal for the club. He set career highs in his first season with Chicago, scoring four goals and providing three assists. Duka began the
2014 season in Chicago, but appeared in just six of the first 19 matches. He did start away to his former club Columbus on May 24, but was subbed off after 61 minutes in a 2–0 defeat. His final appearance with the Fire came on July 6 in a 1–1 away draw with
Sporting KC, when he came on as a substitute at halftime for
Alex.
Montreal Impact On July 29, 2014, Duka departed Chicago when he was traded to the
Montreal Impact in exchange for
Sanna Nyassi. He made his debut for the Impact on August 2, 2014, in a
401 Derby match against
Toronto FC, coming on as a substitute for
Justin Mapp in the 74th minute of a 2–0 defeat. Duka made his first start in Montreal when his former club, the Fire, visited
Stade Saputo on 16 August 2014. He played the full 90 minutes, tallying one shot in a 1–0 Impact victory. In the next MLS match for Montreal, away to the
New York Red Bulls on August 23, 2014, Duka tallied his first goal for the Impact. His left-footed strike in the 37th minute gave the Impact a 1–0 lead at the time, but they went on to fall 4–2 to the Red Bulls. Duka went on to score in matches against the
Houston Dynamo and
San Jose Earthquakes and finished the
2014 season with three goals for Montreal, appearing in all 14 matches after the trade. In the
2014–15 CONCACAF Champions League, Duka appeared in all 10 matches the Impact played in their run to the final of the tournament. He scored twice, with both goals coming in the first leg of the quarterfinal matchup with Mexican side
Pachuca. Duka started both legs of the
2015 CONCACAF Champions League Finals against Mexican side
América. In the first leg, held at the
Estadio Azteca, he received a yellow card and was replaced in the 71st minute by
Maxim Tissot as América's
Oribe Peralta scored in the 89th minute to earn a 1–1 draw. In the second leg, at the
Olympic Stadium, Duka went the full 90 minutes as the Impact were defeated 4–2 and denied their first-ever
CONCACAF title by a 5–3 aggregate score. In the
2015 Canadian Championship, Duka appeared in three of four games for the Impact, only being benched in the second leg of the championship against
Vancouver Whitecaps FC. In the first leg, he had started and played 76 minutes before being replaced by
Andrés Romero. With the 4–2 aggregate defeat, Montreal was denied a berth in the
2015–16 CONCACAF Champions League. Duka opened the
2015 season in the starting lineup, as he went the full 90 minutes of a 1–0 season-opening loss to
D.C. United, but he would wind up starting just 19 of 34 regular-season matches. Duka scored his first goal of the season on May 16 against
Real Salt Lake, his 78th-minute strike helping Montreal to their first MLS win of the season, 4–1. He wouldn't score again until September 19 against
Eastern Conference-leading
New England Revolution. After coming on as a substitute for
Andrés Romero in the 71st minute, Duka chipped Revolution goalkeeper
Bobby Shuttleworth in the 76th minute to seal a 3–0 victory for the Impact. In the
2015 MLS Cup Playoffs, Duka appeared in all three matches for the Impact, but did not finish the full 90 minutes in any. He started the 3–0 victory in the Knockout Round over Toronto FC, before being replaced on 84 minutes by
Dominic Oduro. At home for the first leg of the semifinals against
Columbus Crew SC, Duka came off the bench to replace Oduro in the 61st minute of a 2–1 victory. The second leg at
MAPFRE Stadium would turn out to be Duka's last game with Montreal. His 40th-minute goal would put the Impact up 3–2 on aggregate, but Duka would be replaced by
Hassoun Camara in the 65th minute as Montreal would lose the game, 3–1 in extra time, and the series 4–3 on aggregate. At the end of the 2015 season, Montreal expressed interest in bringing Duka back for 2016, with the player saying, "Now, I’m just waiting for the Impact to make an offer. I’m going to look at that. If that’s good, I’ll definitely come back." However, on January 18, 2016, Duka announced he would not return to Montreal, with the club quoted as saying he wanted to pursue opportunities in Europe. The Impact retained his rights in MLS.
Return to Columbus After leaving Montreal following the
2015 season, Duka returned to Columbus on June 20, 2016, after Columbus acquired his right of first refusal from Montreal in exchange for general allocation money, targeted allocation money, and a second round pick in the
2017 MLS SuperDraft. He made his return to Columbus July 3, 2016, playing 17 minutes as a substitute in a 3–2 win against
Sporting KC. Duka's first goal back with Crew SC came October 1, 2016, in a 3–0 victory over his former club, Chicago Fire. He ended the 2016 season with one goal and one assist in 15 appearances. Duka was waived by Columbus on July 10, 2017.
New York Red Bulls Duka was picked up by the
New York Red Bulls on August 10, 2017.
International Duka played in all three games for the
United States in the
2009 FIFA U-20 World Cup in Egypt. He scored the third goal and gave an assist in the team's 4–1 win over
Cameroon. Duka made his lone appearance with the
U-23 national team on February 29, 2012, against
Mexico, in the lead up to the
2012 London Olympics. He was not selected to the US team for the
2012 CONCACAF Men's Olympic Qualifying Championship, where the United States was eliminated in the group stage. ==Career statistics==