|Date of birth||January 31, 1989|
|Place of birth||Bwiam, Gambia|
|Height||5 ft 9 in (1.75 m)|
|2001–2004||Gambia Ports Authority|
|2004–2007||Gambia Ports Authority||82||(18)|
|2007–2013||New England Revolution||104||(8)|
|* Senior club appearances and goals counted for the domestic league only and correct as of October 29, 2016.
Nyassi was scouted by New England Revolution head coach Steve Nicol while playing in the 2007 FIFA U-20 World Cup, and signed with the Revolution shortly thereafter along with his Gambian teammate, Kenny Mansally.
He made his MLS debut on September 9, 2007 against D.C. United as a substitute, playing the final eight minutes on the right wing. He made his first start and scored his first MLS goal on March 29, 2008 in the Revs' 3-0 opening day victory over Houston Dynamo.
Nyassi has represented his nation at various youth levels. He played for the Gambian U-17 national team in the 2005 U-17 world championships, and for the U-20 national team in the 2007 U-20 FIFA Championships. He scored his first goal for the Senior national team on September 4, 2010 in the 2012 Africa Cup of Nations qualification match against Namibia.
|1||September 4, 2010||Independence Stadium, Bakau||Namibia||
||2012 ANC qualification|
New England Revolution
- Lamar Hunt U.S. Open Cup (1): 2007
- North American SuperLiga (1): 2008
- Lamar Hunt U.S. Open Cup (1): 2013
- "Nyassi Set to Sign with the Eddies". February 10, 2015.