The COVID-19 outbreak in Baltimore has led the NFL to postpone the Baltimore Ravens-Pittsburgh Steelers game for a second time.

The Ravens will now play at the undefeated Steelers on Tuesday night at 8 ET, the NFL announced.

Baltimore was scheduled to play host to the Dallas Cowboys on Thursday night, but that game also has been moved, to Monday, Dec. 7, at 5 p.m. ET.

"We appreciate the efforts of the NFL and Pittsburgh Steelers throughout this process, while we all work to create an environment that keeps the health and safety of everyone involved at the forefront of each decision," Ravens coach John Harbaugh said in a statement. "Our organization has a plan in place, and we will be prepared to play the Steelers. We thank everyone for their adaptability and look forward to the challenge of facing a very good football team at Heinz Field on Tuesday night."

This is the third time in the Super Bowl era that an NFL game will be played on a Tuesday. It happened in Week 5 this season when the Buffalo Bills-Tennessee Titans game was postponed because of a coronavirus outbreak in Tennessee. It also occurred in 2010 when a blizzard in Philadelphia shifted an Eagles-Minnesota Vikings game.

The Ravens and Steelers were originally scheduled to play on Thanksgiving night. The NFL moved the game to Sunday after several Ravens players tested positive in consecutive days.

At least 12 Ravens players have tested positive for COVID-19, including reigning NFL MVP Lamar Jackson. The Ravens placed Jackson, Pro Bowl fullback Patrick Ricard, defensive lineman Justin Madubuike and long-snapper Morgan Cox on the reserve/COVID-19 list Friday, adding to eight players placed on the list previously this week.

With Jackson quarantining for 10 days, quarterback Robert Griffin III will start against Pittsburgh. Jackson would be available to start against the Cowboys if he tests negative by next week. That means Jackson would have to miss only one game, thanks to the rescheduling.

Harbaugh told his players Thursday that they wouldn't be allowed to return to the team facility until Monday at the earliest due to safety concerns.

The Ravens have had only two days of walk-throughs this week. Baltimore has been limited to virtual meetings since its team facility was closed at noon Tuesday.

The Steelers canceled practice Friday as they awaited clarification from the NFL. Coach Mike Tomlin also canceled Thursday's practice, but the team is expected to practice Saturday. The Steelers were last on the field together Wednesday.

The Steelers also made additions to the reserve/COVID-19 list Friday, adding Isaiah Buggs, Jerald Hawkins and Stephon Tuitt. Tuitt is the only starter among the group; it's Hawkins' second time on the list.

This isn't the first time the Steelers have dealt with shifting schedules this season. In Week 4, the Steelers-Titans game was initially postponed from Sunday to "either Monday or Tuesday" of that week as the Titans fought to control their own COVID-19 outbreak. The league eventually pushed the game back even more, rearranging the schedule for the Steelers and Titans to play in Week 7 and the Steelers to face the Ravens in Week 8. With the shuffle, the Steelers' bye moved from Week 8 to Week 4.

The Cowboys will also alter their practice schedule with the shift in kickoff, although coach Mike McCarthy was not aware of the game-day change when he met with the media Friday.

After the death of strength and conditioning coordinator Markus Paul, McCarthy wants his team to get away from football. Players are off Friday and Saturday.

"I think it's important for them to be with their family," McCarthy said. "If we did move to Sunday, I wouldn't anticipate us going into a normal seven-day week where I would just treat this weekend and probably Monday, Tuesday like a bye week. I think our team could use that. I have no idea what's going to happen."

ESPN's Brooke Pryor and Todd Archer contributed to this report.