Steffen took over in goal from New England's Matt Turner, who started the first four qualifiers. Steffen, Ederson's backup at Manchester City, used to play for Columbus' Major League Soccer team at old Crew Stadium.
Steffen and Richards increased U.S. qualifying debuts to 23 in five matches this cycle, trailing only 1998 (29), and 2006 and 2010 (26 each). Richards was making just his fourth international appearance.
Musah is the only American to start all three October qualifiers.
Goalkeeper Sean Johnson, defender Shaq Moore and midfielder Sebastian Lletget did not dress.
Costa Rica coach Luis Fernando Suárez made two changes, forced by the absences of forwards Joel Campbell (sprained right ankle) and José Guillermo Ortiz (positive COVID-19 test). He inserted Ricardo Blanco as part of a five-man back line along with forward Jonathan Moya.
They joined right back Keysher Fuller, central defenders Óscar Duarte and Francisco Calvo, left back Rónald Matarrita, and midfielders Celso Borges, Yeltsin Tejeda, Bryan Ruiz and Johan Venegas.
The match was played at Lower.com Field, the $300 million-plus downtown home of the Columbus Crew that opened in July on the banks of the Scioto River.
The U.S. began the night with eight points, second to Mexico (11) and ahead of Panama on goal difference. Canada (seven) was fourth, followed by Costa Rica (six), El Salvador (five), Honduras (three) and Jamaica (two).
The top three nations in North and Central America and the Caribbean qualify from the 14-match round for next year's World Cup in Qatar, and the No. 4 team advances to a playoff.
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