Ayton (knee) has been ruled out for Friday's game against Dallas, Danny Marang of 1080 The Fan Portland reports.

Ayton was carrying a doubtful tag prior to this update, so it's not a surprise to see him miss his second straight contest. Duop Reath started in Ayton's absence Wednesday against the Warriors and produced 10 points, six rebounds, two assists, one steal, one block and one three-pointer in 22 minutes. Ayton's next chance to play is Monday against the Clippers.