Miller was visibly in pain throughout Sunday's contest despite trying to play through an injury, and Adam Jahns of the Chicago Sun-Times reported on the extent of the setback after the game.
In his first NFL season, the 23-year-old is producing to the tune of eight receptions for 60 yards and a touchdown through three games.
Miller was part of Chicago's efforts to overhaul its receiving corps during the offseason, as it selected him with the No. 51 overall pick in the second round of the 2018 NFL draft out of Memphis.
No wideout in the draft was more productive during the 2016 and 2017 seasons than Miller. In each of those campaigns, he caught 95 or more passes for over 1,400 yards and at least 14 touchdowns.
The 2017 season was Miller at his best, as he reeled in 96 receptions for 1,462 yards and 18 touchdowns, all of which were career highs.
In hopes of helping the development of young quarterback Mitchell Trubisky, the Bears placed a great deal of emphasis on getting him more weapons through free agency and the draft.
Along with the selection of Miller, Chicago signed wide receivers Allen Robinson and Taylor Gabriel, as well as tight end Trey Burton.
The Bears also allowed wide receivers Cameron Meredith, Dontrelle Inman, Kendall Wright and Markus Wheaton to depart.
Most of Chicago's receivers excel on the outside, but Miller is a major asset for Chicago because of his ability to get open both outside and out of the slot.
Provided Miller lands on the shelf, Robinson and Gabriel will likely be the top wideouts expected to pick up the pace, while Kevin White might also take on a greater role after several injury-plagued seasons.
Chicago is in a much better spot now in terms of receiver depth than it was last season, but Miller still represents a big loss because of his reliability.