On December 23, 2006, Haydar picked up a point in his 32nd consecutive game, breaking the record for the longest AHL scoring streak.

Darren also played as a reserve forward with the Thrashers and scored his first NHL goal on October 13, 2007, against Martin Brodeur in a 6-5 loss to the New Jersey Devils.

[13] A free agent at season's end, Haydar signed an AHL contract to return to the team he formerly captained, the Chicago Wolves on July 28, 2010.

After three further seasons with the Wolves, Haydar left North America for the first time in his career and signed a one-year contract in Europe with EHC München of the DEL on July 25, 2013.

[16] Upon completing a single season in the DEL on June 9, 2014, he signed a one-year contract, along with former Wolves teammate, Jason Krog, in the Kontinental Hockey League with Croatian club, KHL Medveščak Zagreb.

After showing early scoring touch in Villach, Krog and Haydar both opted to remain signing a one-year contract on October 15, 2014.

[18] In the off-season, Haydar left Villach as a free agent and returned to play for a second stint in Germany after signing with Lausitzer Füchse of the DEL2 on September 28, 2015.

[21] He later concluded his professional career in accepting a position as a sales representative at a real estate entity in Milton, Ontario, working alongside his older brother Ryan, who was also a hockey player but now has officially retired.

[24] After first experiencing symptoms in 2012, Haydar was diagnosed over a year later with multiple sclerosis and has organized a charity golf tournament in support of the MS Society of Canada’s Hamilton-Halton Chapter since 2017.