The clubs swapped midfielders in their mid-20s as a spate of MLS trades continued Tuesday.
Nyassi, a 25-year-old Gambian international, scored three of his 15 MLS goals when he notched a hat trick for Colorado in 2010. He is yet to replicate that feat or display the same attacking prowess he did in 2010, but the Fire hope he can help the club continue its playoff push.
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“Sanna is a versatile, attack-minded player who will provide depth and strengthen our squad as we embark on the second half of the season,” Fire head coach and director of soccer Frank Yallop said in a news release. “I’d like to thank Dilly for his time in Chicago and wish him well as he heads to Montreal.”Sitting at the bottom of the table, Montreal will hope Yallop's good tidings turn true. Duka was a regular last season but made only six starts this year.