2012: Willis made appearances in 11 games in his second season with United, starting 10 of them. Willis made 31 saves – a career high – in 972 minutes in the 2012 season. Willis registered 2 shutouts for the Black-and-Red, both in 0-0 ties to Vancouver Whitecaps FC on 3/24 and Seattle Sounders FC on 4/7. In Leg 2 of the Eastern Conference Semifinals, Willis enter the game to save a re-taken penalty kick en route to a 1-0 series-clinching win against the New York Red Bulls.
2011: Willis made his MLS debut on 8/13 in the 4-0 win against expansion side Vancouver Whitecaps FC. The University of Denver graduate had a memorable first outing for the Black-and-Red, recording six saves and earning his first career win and shutout. Willis played three matches (three starts) for United, registering one shutout and 12 saves in 270 minutes of action during the 2011 MLS season.
2010: Joe Willis started 12 games for the University of Denver Pioneers his senior season, recording four shutouts. He made 64 saves for a 0.877 saves percentage. He also faced 203 shots, allowing only nine goals for a 0.72 goals against average. To cap off his season, Willis was named All-MPSF.
2009: During his junior year, Willis led the Pioneers by playing in 19 games and recording four shutouts, compiling a 0.737 save percentage. He was named MPSF Player of the Week for the week of September 28, as well as being named to the Big West Challenge All-Tournament Team and the All-MPSF First Team.
2008: Willis’ sophomore season saw him start 15 games, making 71 saves while only allowing 17 goals for a 0.807 save percentage. He finished the season with a 1.18 goals against average. Willis was named team MVP, as well as being named to the All-MPSF First Team and the NSCAA Division I Men’s Soccer Far West All-Region Third Team.
2007: Willis redshirted the 2007 campaign.
2006: Willis started five games and compiled a 3-1-1 record with three shutouts and only allowed three goals as a freshman.
Willis played club soccer for St. Louis Scott Gallagher, where he led his team to three consecutive state championships between 2004 and 2006. He also played in the USL Premier Development League with the Real Colorado Foxes.
Selected in the third round (50th overall) of the 2011 MLS SuperDraft on 1/13/11.