NWSL players briefly halted matches on Wednesday in a display of solidarity with players who have made sexual misconduct allegations against a coach.
NWSL games were suspended, while league commissioner Lisa Baird resigned.
On Wednesday, Portland Thorns, who Riley previously managed, announced general manager Gavin Wilkinson had been placed on administrative leave.
The Thorns previously apologised for their lack of transparency after receiving a complaint about Riley in 2015.
As the league resumed, Wednesday’s three matches were paused in the sixth minute, with both teams at each match linking arms in the middle of the pitch.
In a statement, the NWSL Players’ Association said: “Players will join together in solidarity at the centre circle for one minute in recognition of the six years it took for Mana [Shim], Sinead [Farrelly], and all those who fought for too long to be heard.
“We call on fans to stand in silence with us. During that time, we ask you to stand in that pain and discomfort with us, as we consider what too many of us have been asked to sit with for too long.
“We call on you to consider, in that minute, what is demanded of each of us to reclaim our league and our sport.”
The NWSL, US Soccer and world football governing body Fifa are to conduct separate investigations into the allegations.