W-League: Washington Freedom Futures and DC United Women, 2010–11 In 2010, Nairn played for the
Washington Freedom Futures in the
W-League. In 2011, Nairn signed with
D.C. United Women in the
W-League. She made four appearances, scoring three goals and providing one assist notching seven points for the season. She scored twice in a game against the
New York Magic leading the team to its first win in franchise history.
ASA Chesapeake Charge, 2012 In 2012, she played for the
NCAA-compliant semi-professional club,
ASA Chesapeake Charge, in
WPSL Elite. She played in three games and scored one goal.
Seattle Reign FC, 2013, 2017 prepare for a free kick during a match against the
Portland Thorns FC on May 25, 2013|right On January 18, 2013, Nairn was drafted to the
Seattle Reign FC as the seventh pick (first round) of the 2013 NWSL Draft. On her signing, Nairn said, "It's a great opportunity, like I said before, to represent Seattle and where I've come from – Penn State, and all the teams I played for before. To represent them on a professional stage is a dream come true. I'm excited to get to work." Nairn scored the first regular season goal for the Reign during the team's first league match against
Chicago Red Stars on April 14, 2013, with a diving header on a cross from forward,
Liz Bogus. Nairn led the team in assists and was a leading-scorer. She finished the
regular season with five assists and three goals. Nairn returned to the Reign for the 2017 NWSL season. She appeared in all 23 matches, having 21 stars.
Washington Spirit, 2014–2016 On November 20, 2013, the Seattle Reign traded Nairn to the
Washington Spirit for the discovery rights to Scottish international
Kim Little. In 2014, she scored six goals and took 52 out of 76 corner kicks for the Spirit. In 2015, Nairn scored five goals and recorded two assists. In her third year with the team, the midfielder was voted Spirit MVP for her contributions to the first ever NWSL Championship appearance for the Spirit. She played every match for the Spirit in 2016, starting 18 in the regular season and both post season matches, and scored three goals. Her goal against the
Houston Dash on August 18 earned her the NWSL Goal of the Week honors in Week 16. Nairn's most memorable assist of the season came in the semifinal on
Francisca Ordega's game-winning goal to send the Spirit to the NWSL Championship.
Melbourne Victory, 2014–2019 In September 2014, Nairn went on loan to the
Melbourne Victory for the
2014 W-League season. She returned for the
2015-16 season and
2016-17 season. After taking a season off she returned to the Victory for her fourth loan spell with the club in the
2018-19 W-League season. She won the W-League Premiership in 2018–19. She subsequently received the
Julie Dolan Medal, becoming the first international player to receive Australia's W-League player of the year award.
Houston Dash, 2019–2021 On February 26, 2019, Orlando Pride traded Nairn to the
Houston Dash for exchange for an international slot and draft picks. On October 12, 2019, she became the first NWSL player to make 150 league appearances. She retired from professional soccer on September 18, 2021, after a friendly match against
Tigres UANL ==International career==