Green is not currently scheduled to undergo surgery and the best-case scenario for a return is believed to be seven to eight weeks. However, everything is pending a second opinion on Monday, Pelissero reported.
Bengals coach Zac Taylor would not confirm that timetable when addressing the media after Sunday's practice but did note he'd have a better idea of the 30-year-old receiver's status Monday after further testing.
"We don't know that (it'll be 7-8 weeks) yet. We'll gather more information. It looks like an ankle sprain. The severity of it, we don't know. ... But the good news is, it doesn't appear to be anything that's extremely long term. That's the good news based on what I saw yesterday. Your heart drops a little bit."
This is the third time since 2016 that an injury has threatened Green's season. It was in that year that Green tore his hamstring in Week 11 and missed the remainder of the season.
After a bounceback 2017 campaign, Green played a career-low nine games in 2018 after suffering a toe injury in Week 8. He missed the next three games and returned in Week 13 only to reaggravate the injury and move to season-ending IR in December. His 2018 totals were 46 receptions for 694 yards -- both career lows -- and six touchdowns.