Rosario continued to have a successful 2010 season for Toronto, culminating in a spot on the MLS All-Star team, scoring a goal in the 5–2 loss to Manchester United. On August 3, 2010, De Rosario scored against C.D. Motagua in the second leg of Toronto FC's CONCACAF Champions League preliminary round tie, which at the time, put TFC ahead on 2–1 on aggregate. They would eventually win 3–2 on aggregate. On December 28, De Rosario was confirmed to be on trial with Scottish Premier League club Celtic by manager Neil Lennon. Dwayne and Celtic inquired about the possibility of a short-term loan deal until the MLS season kicked off in March, however new Toronto FC coach Aron Winter and the league denied any further negotiations. De Rosario scored the first Toronto goal of the 2011 season on March 19 in a 4–2 away defeat to Vancouver Whitecaps FC in what was the league's first all Canadian match up. The goal scored in the 20th minute was also the 8000th goal scored in Major League Soccer's history. New York Red Bulls New York Red Bulls acquired De Rosario on April 1, 2011, in exchange for midfielder Tony Tchani, defender Danleigh Borman and a first round 2012 MLS SuperDraft pick. He scored his first goal for New York on a penalty, as the second goal, in a 3–2 loss to Chivas USA. D.C. United D.C. United acquired De Rosario on June 27, 2011, in exchange for midfielder Dax McCarty. He scored his first goal for the club against his former club New York Red Bulls on his return to Red Bull Arena. On July 30, 2011, his double gave United a 2–0 victory over former club, San Jose. On August 6, 2011, he led United to a 3–3 draw against Toronto F.C. with his hat-trick. All three goals were scored while United played with ten men following an early ejection of goalkeeper Bill Hamid. His second hat-trick was recorded on September 25, 2011, as he recorded all three goals in the span of 9 minutes, setting another MLS record. De Rosario completed the season with a total of 16 goals and 12 assists over 32 games. Of those, 13 goals and 7 assists were made during his 17 games with United. On August 29, 2012, De Rosario scored his 100th MLS goal, in a 2–2 home draw against the Red Bulls. He