Milliner sustained a high ankle sprain during practice on Aug. 10 and has been out since.
On Monday, Ryan had said he hoped Milliner would be able to play Week 1.
Cornerback Antonio Allen has already been told he will start on Sunday after being medically cleared on Tuesday. Allen recently converted to the position from free safety because of the Jets' depth issues at cornerback.
Milliner started 12 games for New York last season, grabbing three interceptions and making 56 tackles.
- Molly Geary