OWINGS MILLS, Md. (AP) — The Baltimore Ravens knew their defense was going to better this year, and their season-opening shutout of Cincinnati seemed to bear out that assessment.

After forcing five turnovers and getting five sacks in a 20-0 rout, they still believe there is room for improvement.

"We can build on that," coach John Harbaugh said Monday. "We can always work on the things that we need to work on to chase perfection."

After the Baltimore defense wore down in the latter stage of the 2016 season, general manager Ozzie Newsome focused his attention on adding talent and depth to a unit that has long been the team's calling card.

He retained tackle Brandon Williams with a $54 million contract, signed free agent defensive backs Brandon Carr and Tony Jefferson and drafted cornerback Marlon Humphrey with the 16th overall pick.

All four played pivotal roles in harassing Bengals quarterback Andy Dalton and securing Baltimore's first shutout since Nov. 16, 2009, against Cleveland.

But the day belonged to 34-year-old Terrell Suggs, who finished with six tackles, two sacks and a forced fumble. Instead of crowing about the fabulous play of the defense, the standout linebacker bemoaned the few plays in which the unit underperformed.

Suggs said the defense is still a little upset about the bad things that happened.

"Me personally, I (messed) up on a particular play that almost cost us," he said. "By the grace of God, we had 10 other Ravens on the field and it didn't cost us."

He was referring to a 27-yard completion to A.J. Green on a third-and-1 early in the fourth quarter.

"That's my guy," Suggs said.

Told of Suggs admission, Harbaugh said with a grin: "I saw two things for Suggs. He said one, I saw two."

Harbaugh will almost certainly point out each mistake to Suggs when the team reviews the film, simply because the goal is to get better every week.

Suggs knows this too well.

"It's a good place to start, but you can't be satisfied," Suggs said. "I'm in Year 15, and I've seen it all, with all kinds of starts and all kinds of finishes. It's good to take one."

Coming off a back injury that kept him sidelined for the entire preseason, Ravens quarterback Joe Flacco didn't complete any of his three passes in the second half. It wasn't because he was ailing; rather, it was because he didn't have to.

"It's a good way to win," Harbaugh said.

Cincinnati ran 58 plays, only a handful of which were effective.

"I think they had half of their yards on five plays," Harbaugh noted. "Popped a couple runs against us, a couple zone runs, and they hit a 7-route pass on us and hit a screen. So those are plays that we look at real hard and try to clean those things up while we anticipate what's coming next from our next opponent."

The Ravens next face the Browns, who opened their season with a 21-18 loss to Pittsburgh.

Perhaps the only downer about Sunday's frolic in Cincinnati was injuries to two key players: running back Danny Woodhead (hamstring) and backup linebacker Za'Darius Smith (knee). Harbaugh was awaiting the results of MRIs on both players, but said Woodhead's injury involves "a timeline" and it did not appear as if Smith's knee sustained structural damage.

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