“Entourage” star Adrian Grenier and his girlfriend, Isabel Lucas, have broken up, a source informed PEOPLE magazine.

It seems that the two ended their relationship about three weeks ago, not long after Isabel Lucas and Shia LaBeouf’s car accident, which left the latter with a crushed hand. PEOPLE cited the unnamed source as saying that things weren’t working anymore between the two actors and that the “hanging out” between Lucas and her “Transformer 2” co-star was one of the break-up’s main reasons.

Isabel Lucas, aged 22, was the passenger in Shia LaBeouf’s vehicle at the time of the accident, which took place on July 27. However, she was not severely hurt and after being treated for minor contusions and bruises at the hospital, she was released. Lucas recently told Access Hollywood that her co-star was recovering and “his hand is healing well.”

Rumors have it that Lucas and Grenier, aged 32, had been dating for several months. A representative for the actress informed PEOPLE that Lucas was single.

A representative for Adrian Grenier was not immediately available for comment.

Nevertheless, it looks like both actors got over the break-up in no time. Isabel Lucas was spotted hanging out with Shia in L.A. on Monday, while her supposed ex was seen swimming with a blonde hottie.