Here’s a spine-chilling thought for NFL defensive backs: Antonio Brown is getting even better.

In preparation for the upcoming season, Brown has been working with renowned wide receiver trainer David Robinson, whose client list includes players like Emmanuel Sanders and Josh Doctson.

Brown posted one clip from a recent session that really caught our eye:

[instagram src=”https://www.instagram.com/p/BIU4LxThqYv/”]

As you can see, Robinson has wrapped a towel around AB’s arm and tries to pull his arm as he goes to make the catch. This is a great way to simulate the resistance and contact Brown must overcome to make catches in traffic, a skill that often separates elite players from the rest of the pack.

Any pass-catcher can use this drill in his training. Just be sure that the towel-puller doesn’t pull so aggressively that he causes an injury.

RELATED: Once Labeled “Too Skinny,” Josh Doctson Now Has The Jacked Arms of a Linebacker

That wasn’t the only drill Robinson had Brown perform. Check out his butter-smooth footwork and sticky hands in these clips:

In the lab with my guy @AntonioBrown84 Pittsburgh Steelers WR “Business is Boomin” Come train like a Pro!!! pic.twitter.com/VPzq5K2ORr

— David Robinson (@drobsports1) July 26, 2016

In the lab in Miami grinding with my man Antonio Brown Pittsburgh Steelers WR “Train like a Pro” pic.twitter.com/swCb4lmL7z

— David Robinson (@drobsports1) July 25, 2016

Brown’s intelligent route-running makes him one of the toughest covers around, and his ability to rack up yards after catches can infuriate defenses. His 136 receptions in 2015 tied him with Julio Jones for the most in the NFL, and his 1,834 receiving yards ranked second. He also had a minuscule 1 percent drop rate, according to SportingCharts.com.

Could 2016 be the year when AB finally breaks the mythical 2,000-yard mark? Based on his track record and his intense off-season training, it’s certainly not out of the question.

RELATED: We Dare You To Try Antonio Brown’s Off-Season Conditioning Workout