The Cincinnati Bengals are hoping to bounce back from a strange end to their four-game win streak but they'll have to overcome a rash of injuries, mainly on defense.
Atkins, who had a team-best six sacks and a career-high 12 1/2 in 2012, joins cornerback Leon Hall (Achilles), safety Taylor Mays (shoulder) and defensive end Robert Geathers (elbow) on injured reserve.
Middle linebacker Rey Maualuga (knee, concussion) and offensive tackle Andrew Whitworth (knee) didn't play last week and both were held out of practice Wednesday. Running back Giovanni Bernard, though, returned to limited practice after hurting his ribs late against Miami and backup middle linebacker Michael Boley was back after missing that loss because of an ailing hamstring.
With Atkins out, second-round draft pick Margus Hunt is expected to play a little more on the inside for the Bengals, who have a two-game lead over second-place Cleveland in the AFC North.
"We can't get hung up on (injuries). I showed our guys the last four or five Super Bowl champions and the amount of people that went on IR. They overcame it," coach Marvin Lewis said. "The best team in the NFL year after year finds a way to overcome all the obstacles that come along the way.
"The playmakers of the team have to step up and win."
That means more production from Dalton, who extended his streak of 300-yard games to four last week, but didn't throw a touchdown and was picked off three times. He had totaled 11 TD passes and two interceptions in his previous three games.
After some extended rest, Lewis' team will try to persevere against Baltimore (3-5) before hosting the Browns.
''Honestly we feel like these next two weeks are the biggest of the season because of where we are in the division," Whitworth said. "We get an opportunity. These games can tilt things one way or the other."
The Ravens have been on the wrong end of several close calls, losing their last three by a combined 11 points.
They cut an 11-point deficit to three early in the fourth quarter last Sunday in Cleveland but allowed the Browns to cap a 15-play drive with a field goal with 14 seconds to play in a 24-18 loss. Last season, Baltimore won eight games by seven points or fewer, including two in the playoffs, en route to the franchise's second Super Bowl title.
"It's the National Football League. Most all the games are going to be close,'' coach John Harbaugh said. "The difference is winning the close games. We've done that in the past. We have to do that again. That's what we have to figure out how to do. "
The Ravens, who haven't lost four in a row since dropping a team-record nine straight in 2007, are averaging 17.0 points in the last three games after scoring 23.4 per contest to start the season. Baltimore is averaging just 61.3 rushing yards during its losing streak and 71.6 this season after producing 118.8 per game in 2012.
The passing game hasn't been much better, as Joe Flacco has already been sacked 25 times - 10 fewer than all of 2012.
Starting strong has been another problem for Baltimore. The Ravens scored their only first-quarter touchdown in the season opener against Denver and have been outscored 92-63 in the first half. They've outscored opponents 71-36 in the fourth quarter.
"Let's come out of the gates. Let's find a way to get a lead," Harbaugh said. "We have not been able to do that.
"Offensively, we've just got to get better. I've got a lot of optimism that we'll do it as a team. But we'd sure like to get it going and build some confidence and see our guys starting to make plays."
Cincinnati snapped a four-game skid in the series with a 23-17 home win Dec. 30 but both teams were resting their starters for much of the game after securing playoff berths.
Cincinnati has lost in each of its last three visits to Baltimore and was blown out 44-13 in its latest one Sept. 10, 2012.
Prior to seeing limited action in last December's meeting, Ray Rice had rushed for two touchdowns in each of his previous three games against the Bengals. Rice has just three touchdowns this year - and none in the last three games - and with 259 rushing yards, he's on pace to end his streak of four straight seasons with at least 1,100.