Report: Johnny Manziel dropped by Nike after 2015 season ended

The losses keep stacking up for troubled NFL quarterback Johnny Manziel, who has been dropped by his biggest sponsor, Nike, according to ESPN.

A Nike spokesperson told ESPN that Manziel, who signed a multiyear deal with the company in March 2014, is no longer affiliated with the brand.

In January, TMZ reported that Nike was "on the fence" about retaining Manziel as a brand endorser, and ESPN reports that Nike cut ties with the former Browns quarterback some time after the 2015 NFL season ended.

The former Heisman Trophy winner was dumped by his original agent, Erik Burkhardt, back in January; on Tuesday, Manziel was fired by agent Drew Rosenhaus. Both agents severed their relationships with Manziel after he refused to enter treatment for his ongoing off-the-field issues.

Manziel is under investigation for an alleged domestic violence incident with his ex-girlfriend, Colleen Crowley. The case is scheduled to be presented to a grand jury on Thursday, with a ruling coming as soon as Monday. The NFL is also investigating the incident to determine if Manziel violated the league's personal conduct policy.

In recent weeks, Manziel has been spotted displaying questionable behavior at various party scenes, including Las Vegas and Los Angeles night clubs and most recently the Coachella music festival.