The NFL kicked off its investigation into allegations leveled against Jameis Winston last week by speaking with the Tampa Bay Buccaneers' head of security, Andres Trescastro, a league source told ESPN.

The investigation is not expected to be wrapped up by the end of this season, according to a source. Winston's case could hang over the upcoming NFL offseason similar to how Ezekiel Elliott's case extended through this past NFL offseason.

The NFL's conversation with Trescastro was more introductory and exploratory, as the league explained how it is going to be looking into the accusation that Winston groped a female Uber driver in Arizona on March 13, 2016. There are no further talks planned at this time, but the investigation will continue.

The driver has hired attorney John Clune, who also represented the Florida State student who accused Winston of sexual assault in 2012.

Clune has asked the NFL to also investigate a claim made by Philadelphia Eagles cornerback Ronald Darby, a college teammate of Winston's who released a statement last Sunday saying that the Buccaneers quarterback did nothing inappropriate with the driver.

Clune tweeted that he has demanded that Darby "immediately turn his phone over to the NFL so the GPS history can be forensically examined."

The driver, who declined to give her name, told BuzzFeed News earlier this month that Winston reached over and "grabbed" her crotch for three to five seconds while the car was stopped at a drive-thru restaurant. She also told BuzzFeed News that Winston was the only passenger in the car and said that she reported the incident to Uber at the time.

Winston has denied the allegation, saying that the driver "was confused as to the number of passengers in the car and who was sitting next to her." Darby also stated that there were three passengers in the car and that he and Winston were sitting in the back seat.

Police in Phoenix and Scottsdale, Arizona, told ESPN's Jenna Laine earlier this month that they were not contacted at the time about any incidents involving Winston and an Uber driver.

Winston will miss his third straight game Sunday against Atlanta because of a shoulder injury.