More drama involving Terrelle Pryor and his ex-GF, Shalaya Briston ... TMZ Sports has learned the former NFL star was arrested Wednesday after he allegedly slapped her and threw pumpkins at her car.

According to police documents, Pryor got into an argument with Briston -- the woman accused of stabbing the wide receiver back in 2019 -- in Pennsylvania at around 1 AM following a night out drinking.

In the docs, cops say Pryor had been out with Briston, but returned home while Briston continued on to another bar.

While home, according to cops, Pryor got upset with Briston and blew up her phone ... calling her over 50 times and sending her more than 30 unanswered text messages.

Cops say Briston eventually returned to Pryor's residence, but stayed outside "out of fear of Pryor."

In the docs, police say Pryor came outside and confronted Briston, shoving her and then slapping her in the face with an open hand.

Cops say as Briston tried to flee ... Pryor threw a deck chair at her. Officers add that when she got into her Mercedes, Pryor then threw pumpkins at her car, causing damage to the windshield.

Police say Briston had "inflammation, redness and bruising under her left eye" ... and Pryor was ultimately arrested.

Officers noted in the docs that Pryor denied hitting the woman ... but did admit to throwing the pumpkins.

Court records show the 32-year-old has been charged with simple assault, harassment and criminal mischief. The records show his bail has been set at $100K.

Of course, this is far from the first wild incident involving Pryor and Briston ... you'll recall, in Nov. 2019, Briston was arrested after she was accused of nearly stabbing Pryor to death following a night out partying.

Both Pryor and Briston were hit with charges over the incident ... but both cut plea deals in 2020 and were sentenced to probation.

Pryor has since recovered from the stab wounds and had been trying to make a comeback in the NFL.