Coach John Fox said surgery is planned in the near future. Moreno was hampered earlier in the season by a nagging hamstring injury that kept him out of one game and on the sideline for another.
"He's tough-minded and he'll battle back from it," Fox said.
Moments after announcing the injury to Moreno, the Broncos tweeted the team promoted Jeremiah Johnson from the practice squad. Johnson is a second-year player out of Oregon who's never had a carry in the NFL.
But his familiarity with the offense made him a logical choice to bolster a banged-up backfield, especially because the Broncos host the New York Jets on Thursday night.
"He knows the nomenclature, knows the teammates," Fox said. "He's been giving our defense a real good look (in practice), been helpful in getting us better against the run."
Moreno left the game late in the opening quarter when he was tackled near the sideline after a 22-yard run. Moreno, a first-round pick out of Georgia, has rushed for 179 yards on 37 carries this season. He also has 11 catches for 101 yards and one score.
Although Willis McGahee tweaked his hamstring Sunday, Fox said his leading rusher could be ready for Thursday. McGahee didn't go back into the game after hurting his hamstring near the end of the Broncos' opening drive.
"He was cleared to come back into the game. But we weren't going to put him in there unless it was an emergency situation," Fox said. "In part, to have him ready for this Thursday."
McGahee had surgery to fix a broken finger on his right hand a few weeks ago, but returned against Oakland to run for 163 yards and two touchdowns. He had four carries for 17 yards against the Chiefs before exiting.
Third-string running back Lance Ball picked up the slack Sunday in the absence of Moreno and McGahee, carrying the ball 30 times for 96 yards. Tim Tebow did his part in the option offense as well, gaining 43 yards on nine carries.