OWINGS MILLS, Md. -- Darian Stewart, the Baltimore Ravens' new starting free safety, wasn't on the team last year. So you have to take that in consideration when hearing his response about the challenge of covering Cincinnati Bengals wide receiver A.J. Green.

"I don't consider it a challenge. He's just one guy," Stewart said. "We have to make plays when it comes to us and just be aware of where he's going to be at all times."

AJ Green has made the Ravens nuts, as the Pro Bowl receiver tends to have big games against Baltimore. AP Photo/David Kohl

That "one guy" just happens to be the best young receiver in the NFL, and that "one guy" single-handedly drove the Ravens' safeties crazy last season.

Consider this: The Ravens allowed seven completions that traveled at least 40 yards in the air last season, and Green accounted for three of them.

Here were Green's three big plays against the Ravens last season:

On Nov. 10 in Baltimore, Green made a leaping circus catch for 43 yards near midfield. Even though Green was double-covered, quarterback Andy Dalton trusted his three-time Pro Bowl receiver enough to throw the ball anyway. Green made a juggling grab around Ravens safety James Ihedigbo, who was in position to break up the pass.

Green sent that same game into overtime with a 51-yard touchdown on a last-second Hail Mary toss. After the ball bounced off Bengals receiver Marvin Jones, Ihedigbo tipped the pass into the air instead of knocking it down. The ball landed in the hands of Green, who finished with 151 yards receiving.

In the regular-season finale, Green put the Bengals up 7-6 in the first quarter with a 53-yard touchdown. Ravens safety Matt Elam was burned so badly that he tried to hold Green to stop the Pro Bowl receiver from getting downfield and missed on that, too.

The Ravens aren't alone when it comes to struggling to contain Green. Since he entered the league in 2011, Green leads the NFL with 14 catches on passes that have traveled at least 40 yards in the air. He has scored touchdowns on six of them.

The challenge in covering Green -- and, despite what Stewart says, it's a big challenge -- is trying to match his size, speed and athleticism.

"There’s nothing he really doesn’t do well," Ravens coach John Harbaugh said.

The Ravens have wanted to improve their coverage skills at the safety position because they've given up too many big pass plays. That was one of the major reasons why the Ravens cut Bernard Pollard in 2013 and didn't re-sign Ihedigbo this past offseason.

Many thought Terrence Brooks would be the team's starting free safety this season, but the speedy rookie didn't develop quickly enough. The Ravens have gone with Stewart as their starter throughout spring workouts and training camp.

While Stewart isn't the prototypical free safety, he is considered a better fit than Ihedigbo. Stewart said his main job is to keep receivers in front of him, and that begins with Green on Sunday.

"I know the guys up front are going to do their job, so it's up to me to do mine," he said. "I'm counting on me to make plays back there."