Straith played for numerous clubs in Victoria including Bays United, Victoria United, and his Metro Team in the Lower Island Soccer Association, where he was captain.[3] From July 12 to August 3, 2007, he went on trial with the U-19 Junior Bundesliga side of 1860 Munich, along with Antonio Rago.[4] He left Canada in summer 2008, moving to German club Energie Cottbus on a season-long loan deal,[5] after impressing the German club during a one-month trial.[6] In the summer of 2009, Adam left Germany and returned to the Whitecaps but on August 25, 2009 Cottbus exercised its option to sign him for an undisclosed fee.[7]
Professional
Germany
Straith made his senior debut for FC Energie Cottbus in the 2. Bundesliga against FC St. Pauli on October 25, 2009, and scored his first ever goal in Germany in his first game for the club. On December 16, 2009 Straith signed his first professional contract with FC Energie Cottbus tying him to the club until June 30, 2013.[8] He joined 1. FC Saarbrücken on loan in January 2012. He later joined SV Wehen Wiesbaden in 2013.
Fredrikstad
After months without a club, Straith joined Norwegian side Fredrikstad in January 2015.[9]
On August 18, 2017, Straith signed a one-year contract with German 3. Liga side Sportfreunde Lotte, marking his return to Germany after three years.[15] After starting regularly in the 2017–18 season, Straith signed a one-year contract extension to keep him in Lotte until 2019.[16] Straith would excel with Lotte in his second season, captaining the squad and leading them to the fifth best goals against in the league, however offensive struggles resulted in the club being relegated to the Regionalliga.
Hansa Rostock
After two years with Lotte, Straith would sign with fellow 3. Liga club Hansa Rostock on a two-year contract.[17]
He scored his first goal for Canada in Jamaica during the Caribbean Cup, placing the ball in the left corner of the net.
On May 24, 2010, Straith made his senior team debut as an 81st-minute substitute in a 5–0 loss against Argentina at the Estadio Monumental.[18] He played his second game on June 3, 2010 and played 90 minutes vs Venezuela, alongside his teammate Eddy Sidra.[19] He was officially capped by Canada during its World Cup Qualifying match vs St. Lucia on October 7, 2011.
On January 22, 2017, following an injury to goalkeeper Sean Melvin, Straith played the final 35 minutes in net for Canada against Bermuda. Canada would win the game 4–2, with Straith making a few saves and keeping a clean sheet.[22][23] Straith was named to the 2017 CONCACAF Gold Cup squad on June 27, 2017.[24]