Amari Cooper slammed into the proverbial rookie wall last December, failing to top 20 yards in three of the last four games of the season.
Just how serious was the injury?
In a Monday interview with KGMZ in San Francisco, Cooper said he never bothered to watch his rookie-year game tape because "I really wasn't myself."
"I think it affected everything. Me being a receiver, it affected my whole game," Cooper explained. "Talk about a foot injury, you can't release how you want to, you can't come out of your breaks how you want to. You can only get open in two ways, off of the line or out of your breaks.
"So it really affected my game, but I was mentally tough and I fought through it."
The No. 4 overall pick in the 2015 NFL Draft played through a mid-November quadriceps injury and toughed out a lingering foot injury that lasted for months.
In fact, NFL Media Insider Ian Rapoport reported this week that Cooper played most of the 2015 season with a painful bout of plantar fasciitis -- "never complaining, rarely practicing, still performing."
Before the injuries flared up in the second half of the season, Cooper was on pace for 82 receptions, 1,306 yards and eight touchdowns. The first rookie since Mike Ditka in 1961 with three 100-yard performances in his first six career games, he was so dominant by Halloween that NFL Media's Daniel Jeremiah was inspired to pick the Raiders' greenhorn over record-setting Odell Beckham as the young wide receiver with the highest upside.
Prior to Week 12, Carr boasted a 63-percent completion rate at 7.66 yards per attempt with a 24:6 touchdown-to-interception ratio and a 101.5 passer rating. Those numbers plummeted to 56 percent, 5.6 YPA, 8:7 TD-to-INT ratio and a 71.1 passer rating in the final five games.