Ray Rice The Baltimore Ravens, leaders of the AFC North with a 5-1 record, have already begun to look over their shoulders, metaphorically speaking.

Injuries to linebacker Ray Lewis and defensive tackle Haloti Ngata have started to raise questions whether an aging Baltimore defense can continue to perform at a high level for the remainder of the season.

Fans hopeful that linebacker Terrell Suggs' return would give the unit a shot in the arm will have to wait another week, as he has been downgraded to questionable for Sunday’s game against Houston.

The fate of the Ravens’ playoff hopes this season may rest on the arm of Joe Flacco.

Conversely, the Cincinnati Bengals’ playoff hopes may rest on their matchup this Sunday, when they host the Pittsburgh Steelers for the first time in 2012. The Bengals, 1-2 after last week’s loss to the Cleveland Browns, can ill afford to go 1-3 in the division.

The Steelers, coming off a huge 17-16 win against the Philadelphia Eagles in Week 6, have owned the Bengals recently in Paul Brown Stadium, winning 10 of the last 11 meetings. With a victory this Sunday Pittsburgh will be no worse than 2.5 games back of Baltimore, whom they have yet to face this season.

As Week 7 of the NFL season dawns upon the football world, here are five things to watch for in the AFC North?

1) Will a depleted Ravens’ defense be able to stop Arian Foster and the Houston rushing attack?

Historically speaking, the Ravens have had one of the best run defenses in the NFL year in and year out. In 2012, teams have been able to run on Baltimore with relative ease, averaging 136 yards per game. With the aforementioned injuries to Lewis and Ngata, it appears that this unit’s job became that much tougher.

2) Can a much maligned Ravens offense step up against the Texans' defense when it counts?

Before the season began, all the talk centered around Joe Flacco’s transformation into an elite quarterback. Yet in recent weeks, especially against Kansas City, it appeared that the Ravens' offense was missing in action?

Will Ray Rice come up with a big rushing performance in Houston? And can the Ravens' receivers, especially Anquan Boldin and Torrey Smith, provide Flacco with the help he needs?

 3) Can the Bengals avoid falling to 1-3 in the AFC North?

All season long the Cincinnati defense has looked vulnerable. Last weekend it appeared the offense took the week off as well, turning the ball over four times in an embarrassing loss to the previously win-less Browns. As mentioned, the Bengals have not fared well in recent meetings against the Steelers. A win is almost a must if they look to stay in the playoff race.

4) Will Big Ben and the Steelers continue their dominance over the Bengals?

Not only has Pittsburgh won 10 out of the last 11 games at Cincinnati, but the Steelers have enjoyed plenty of success overall against the Bengals when Ben Roethlisberger is at quarterback. 

Roethlisberger enters Week 7’s contest with a 99.9 passer rating, the third highest of his career. The Steelers are counting on Big Ben to once again deliver a big performance in the jungle.

5) Can the Browns keep their momentum from last week going and defeat the Indianapolis Colts?

 The Browns won last year’s meeting between these two teams, 27-19 in Indianapolis against a Colts squad that appeared to be over-matched without Peyton Manning. This year, however, Andrew Luck, not Kerry Collins, will line up behind center for Indianapolis.

Through six games, Luck is on pace to pass for 3,968 yards for the entire season, completely shattering the Colts' rookie quarterback record set by Manning.

For Cleveland, after an abysmal start to the season by Brandon Weeden, the Browns' 29-year-old rookie signal-caller appears to have settled down. Weeden is on pace to pass for almost 4,000 yards himself, yet he needs to cut down on the interceptions if the Browns are to add a few more wins to their record.

 At the end of the day, the team that makes the fewest mistakes on offense should win.