Johnson (hamstring) is expected to be sidelined up to four weeks, Gerry Dulac of the Pittsburgh Post-Gazette reports.
Johnson already appeared likely to miss Monday's game against the Browns after injuring his right hamstring in Pittsburgh's season-opening loss to the 49ers, and based on follow-up exams, he now looks like a potential candidate for injured reserve, if the estimated four-week recovery timetable is accurate. Pittsburgh is on bye Week 6, meaning if Johnson were to miss the next four games, his earliest return date would be Oct. 22 versus the Rams. For however long Johnson is sidelined, George Pickens, Allen Robinson and Calvin Austin will serve as the Steelers' top three wideouts.