[citation needed] Tiffert was signed as a Designated Player for Major League Soccer club Seattle Sounders FC on 27 July 2012,[4] confirming earlier interest and attendance during a game against Sporting Kansas City on 20 June.

[4] He made his debut on 5 August 2012, playing for 26 minutes during a 4–0 victory over the Los Angeles Galaxy, replacing Brad Evans in front of an attendance of 61,000 at CenturyLink Field.

Chivas USA, crossing into the path of a header from Sammy Ochoa, at the Home Depot Center on 25 August.

[10] Tiffert's free kick to Eddie Johnson gave him a second career assist for the Sounders, over Chivas USA at home on 8 September.

[11] Tiffert played for four minutes against Caledonia AIA in Trinidad and Tobago in the CONCACAF Champions League on 31 August.