She played for National Women's Soccer League (NWSL) clubs including the Chicago Red Stars, Seattle Reign, Portland Thorns, Houston Dash, Western New York Flash, North Carolina Courage, and Racing Louisville.

[4] McDonald was a member of the Sereno Soccer club from 2000 to 2007 and helped the team win state championships each year she played for it.

McDonald earned first-team all-conference and all-region honors and was the single-season record holder at Phoenix College for goals and assists.

Also continuing to excel at basketball, McDonald earned first-team all-region and all-conference honors and was the country's number one rebounder in junior college and among the Top 30 in scoring.

[4] After transferring to the University of North Carolina, Chapel Hill during her sophomore year, McDonald joined the North Carolina Tar Heels soccer team during the first half of the 2008 season and helped the squad ultimately win the national championship as a starting striker.

[17] She made nine appearances for the Red Stars during the regular season, serving one assist, before being waived by the team in June 2013.

[20][21] Two games later, during the team's first televised match on Fox Soccer, she scored a brace against the Washington Spirit leading the Reign to a 2–1 win.

[24] McDonald was traded to the Portland Thorns along with defender Rebecca Moros in late 2013 under head coach Cindy Parlow Cone, in exchange for Danielle Foxhoven.

McDonald was a starting forward for the first eleven games of the 2014 season, then mostly relegated to a substitute position as Alex Morgan returned from an injury.

This would be her only season in Portland, where she played as number 14 for a total of 1310 minutes in 24 regular-season games under head coach Paul Riley.

[30] In January 2016, the Western New York Flash acquired McDonald in a trade that sent two international spots and one 2017 draft pick to Houston.

[31] Named Player of the Week for week 10 and to the Second XI list, McDonald finished third in the NWSL overall in goals scored (10), assists(7) shots (61), and second overall in shots on goal (34) for the 2016 season, McDonald earned her first senior team call-up for the USWNT.

[35] On December 17, 2021, shortly before the NWSL draft, Racing Louisville acquired McDonald's playing rights in a three-way trade with the Courage and Angel City FC.

[40] In October 2022, McDonald was loaned to Australian A-League Women club Western United on a three-month guest contract for the start of their inaugural season.

Following a strong 2018 NWSL season, McDonald was called up to the team in November 2018 for the abroad friendlies vs Portugal and Scotland.

In May 2019, McDonald was named to the final roster of the United States 23-player squad for the 2019 FIFA Women's World Cup.