July 21 (UPI) -- Veteran running backs Denard Robinson and Ronnie Hillman worked out for the Dallas Cowboys this week as the NFL continues to investigate Ezekiel Elliott.
Dallas currently has Darren McFadden, Alfred Morris and unsigned rookie Jahad Thomas on their depth chart behind their second-year All-Pro. Versatile backup Lance Dunbar signed this offseason with the Los Angeles Rams.
Hillman, 25, was a third round pick in the 2012 NFL Draft. The San Diego State product played his first four seasons with the Denver Broncos before joining the Minnesota Vikings and San Diego Chargers last season.
His best season came in 2015, when he had 974 yards from scrimmage with seven touchdowns in Denver. The Broncos cut Hillman in September.
Robinson, 26, was a fifth round pick in the 2013 NFL Draft. "Shoelace" played his first four NFL seasons with the Jacksonville Jaguars before his rookie deal expired. The free agent out of Michigan tried out for the Chicago Bears and New York Jets this offseason. He turns 27-years-old in September.
Multiple sources told NFL.com Friday that the NFL Players Association filed a response to the NFL regarding the league's lengthy investigation into Elliott. Sources told NFL.com that the "investigatory part of the process is nearing completion."
The league has already shared its findings with the NFLPA, Elliott and his representatives, according to the report. Sources also told NFL.com that the NFL's report made no recommendation regarding potential discipline for the league's leading rusher from last season.
Sources said earlier this week that the running back could receive a one or two game suspension, according to ESPN. On Thursday, Dan Patrick reported that sources told him that other NFL owners are pushing for a suspension.
No criminal charges have been filed against Elliott in relation to domestic violence claims. The Columbus, Ohio city attorney's office declined to approve criminal charges against Elliott in September. The former Ohio State star met with NFL investigators in October.
Elliott, 21, averaged 5.1 yards per carry last season behind the dominant Dallas offensive line. His backups averaged 3.5 yards per attempt.