Oakland Raiders receiver Martavis Bryant has been suspended indefinitely by the NFL, according to the Mercury News' Matt Schneidman.

"Effective immediately, Martavis Bryant has been returned to the Reserve/Commissioner Suspended list indefinitely for violating the terms of his April 2017 conditional reinstatement under the Policy and Program for Substances of Abuse," the NFL said in a statement, per Schneidman.

Bryant landed on injured reserve earlier this month due to a PCL injury.

Michael Gehlken of the Las Vegas Review-Journal reported in mid-June that the team feared a suspension was looming and believed it to be for violating the league's substance abuse policy. The 26-year-old wideout has been banned multiple times in the past relating to the substance abuse policy, four games for marijuana in 2015 and the entire 2016 season for missing multiple drug tests.

Both of those suspensions came during his time with the Pittsburgh Steelers. Oakland acquired Bryant back in April in exchange for a third-round pick.

Bryant has proven to be an explosive playmaker—when he's been able to stay on the field.

The 6'4", 211-pound receiver averaged 42 catches for 639 yards and 5.7 touchdowns in three seasons in Pittsburgh. However, his numbers have been hampered by the fact he has missed 12 games over those three years, not including all 16 games in 2016.

Back in May, Gruden was excited at the thought of being able to work Bryant into his offense.

"Let me tell you, he brings a different dynamic," Gruden said, via Scott Blair of NBC Sports. "He's 6-foot-4 and he plays it. He's 4.4- (second 40-yard dash) fast and he plays it. We just have to get him wired into the offense and Jordy Nelson's experience and versatility has really been impressive that it's allowed us to do some things in just a few days that is pretty cool. We like our receivers, and we think Martavis will make you think twice about doing some things."

Despite that high praise, Bryant was released at the end of the preseason. Former NFL wideout and current NFL Network analyst James Jones revealed in August (h/t Pro Football Talk's Michael David Smith) that the Oakland coaching staff was frustrated with Bryant's inability to learn the playbook.

While the Raiders cut the veteran ahead of the regular season, they brought him back on a one-year deal less than two weeks later.

"I am just thankful and happy and excited for this weekend and the opportunity to take care of my family; it will not be taken for granted," Bryant told ESPN's Jeremy Fowler following the signing (h/t ESPN's Paul Gutierrez).

He had just 19 catches for 266 yards and zero touchdowns in eight games with Oakland this season.

Now, Bryant will have to take a seat and see his NFL career put on hold once again. If/when he returns, he will have to tread carefully as he is running out of chances to prove to teams they can depend on him.