FRISCO, Texas -- Dallas Cowboys defensive end Randy Gregory has won the appeal of his suspension and will be banned for only the first four games of the 2016 season, a source confirmed to ESPN's Dan Graziano on Sunday.

The NFL initially announced in February that Gregory would serve a four-game ban for violating its substance abuse policy. But after it was revealed in July that Gregory had violated the policy again (either by failing or missing a test), he was facing the possibility of having the suspension extended to 10 games.

The NFL has not yet provided the second-year Cowboys pass-rusher with official notice that his appeal succeeded, a source told ESPN's Ed Werder. Agent Deryk Gilmore filed the appeal, but there was never an actual hearing on the matter, the source said.

The Fort Worth Star-Telegram first reported Gregory's reduced suspension.

A four-game suspension does not mean Gregory will be back with the Cowboys on Oct. 3. The team placed him on the reserve/did not report list at the start of training camp, and the source told Werder that Gregory continues to receive inpatient treatment at a drug rehabilitation facility.

Sources told Werder that Gregory's latest commitment to sobriety played a significant role in the NFL's decision to keep his suspension to four games.

Defensive end Randy Gregory was suspended for a year prior to the 2016 playoffs and has not been around the Cowboys since. Kim Klement/USA TODAY Sports

Gregory would be eligible to play Oct. 9 against the Cincinnati Bengals. Defensive end DeMarcus Lawrence, who led the Cowboys with eight sacks in 2015, also began his four-game suspension Saturday for violating the substance abuse policy.

The Cowboys have remained supportive of Gregory and have a locker for him at The Star, their new practice facility. The Cowboys' biggest need remains at pass-rusher, and Lawrence and Gregory would bolster that group.

At the 2015 NFL scouting combine, Gregory tested positive for marijuana, which put him in the league's drug program. Considered a first-round prospect out of Nebraska, he fell to the second round, where the Cowboys selected him with the 60th overall pick.

The Cowboys and Gregory agreed that he would have a personal handler with him during the season to help him cope with issues related to anxiety.

Gregory played in 12 games as a rookie and did not record a sack. He suffered a high-ankle sprain in the season opener against the New York Giants and missed the next four games. Cowboys coaches credited him with 11 tackles and 16 quarterback pressures to go along with one tackle for loss.

Cowboys linebacker Rolando McClain will miss the first 10 games of the season for violating the substance abuse policy, but his return to the team at all seems unlikely.