But any questions about his confidence should have been answered this week when he felt emboldened enough to grab the chest of his head coach and tweak it during practice. Seriously, does a playmaker at the end of his rope do that?
Apparently Jay Gruden still liked Jackson enough to guess that he'll have a big game against the Saints.
"When you have a chance to put back-to-back-to-back practices together after being out so long, it just makes him stronger," Gruden said, via ESPN. "It makes him feel better mentally to where he can let it go. We saw this week, he really let a few go, running fast like we know he can do. The big thing is to get his confidence back and his speed and ability to stretch and push it. I feel good about the progress that he's made."
As we've seen with speed receivers like Odell Beckham, a hamstring injury is largely personal. Self-confidence is huge when a player is deciding to let himself run uninhibited and clearly, Jackson was still struggling a bit against New England.
Either Gruden is afraid of getting tweaked again, or he saw Jackson turn the corner during practice. He's certainly hoping its the latter, otherwise he'll need to layer up on Monday.