CINCINNATI -- With quarterback Joe Flacco missing the entire preseason due to injury and opening against a division rival on the road, the Baltimore Ravens revisited the bruising, defensive style that has served them well in their history.

Flacco passed for 121 yards and a touchdown and the Ravens' defense forced five turnovers in a 20-0 victory over the Cincinnati Bengals on Sunday at Paul Brown Stadium.

"It was just one of those old-fashioned Ravens games," Flacco said. "It reminded me of one of those games my first year as a rookie."

Flacco shrugged off concerns about him missing the entire preseason schedule and most of training camp with a back injury, and was effective against a Bengals' defense that has been tough on him over the years.

Flacco was 9 of 17 with a touchdown and an interception, but emerged relatively unscathed.

"It's always a tough place to come in here and play," Flacco said. "My back didn't take any hits, but my chin did. Once I got out on the field, it felt normal. I felt at home."

Baltimore rushed for 157 yards on Sunday and averaged 3.7 yards per carry.

"You do what you have to do to win the game," Ravens head coach John Harbaugh said. "Every game is going to play out differently. This was a game where running the ball turned out to be the key."

Baltimore's defense made things rough for Bengals quarterback Andy Dalton, who went 16 of 31 for 170 yards and tied a career high with four interceptions. He also lost a fumble.

"Coming into the game, we knew we couldn't hurt ourselves with turnovers, and obviously we did that," Bengals head coach Marvin Lewis said. "We don't have a chance to pout about it, because we've got to get ready for Thursday (vs. Houston)."

It was the fourth-worst loss for Cincinnati in a regular-season opener. The Bengals also were shut out in an opener for the first time since 1979.

"I don't know if I've ever been in such a disappointing football game," Lewis said.

Flacco completed his first five pass attempts on the Ravens' initial possession as they drove 57 yards in 14 plays, capped by a 25-yard field goal by Justin Tucker to put them ahead 3-0.

Running back Joe Mixon made his NFL debut on the Bengals' second series with 19 yards on three carries and one reception. But the promising drive stalled when Ravens linebacker Patrick Onwuasor tipped a Dalton pass into the arms of cornerback Brandon Carr for his 16th career interception, but only his second since 2013.

"Two were tipped balls," Lewis said of Dalton's four picks. "Those didn't bounce our way."

But, another interception, this time by Ravens linebacker C.J. Mosley in the end zone, stalled another long Cincinnati drive.

After Flacco was sacked by defensive tackle Geno Atkins in the second quarter to force a punt, the Bengals couldn't cash in.

With 1:52 left in the half, Flacco hit wide receiver Jeremy Maclin on a quick slant resulting in a 48-yard touchdown that put Baltimore ahead 10-0.

"I think Ben (tight end Benjamin Watson) did a really good job getting a rub with Jeremy's guy, and Jeremy took it from there," Flacco said.

Maclin had two catches for 56 yards and the touchdown.

Dalton's third interception was disastrous for Cincinnati as linebacker Terrell Suggs tipped a pass high in the air and into Lardarius Webb's hands at the 2-yard line. Terrance West's touchdown run made the halftime score 17-0.

West rushed for 19 carries for 80 yards and a score.

Bengals linebacker Nick Vigil began the second half by intercepting Flacco's pass at the Ravens' 26-yard line.

But, the Ravens' defense came up with another big play when Suggs swatted the ball out of Dalton's hand for a fumble that was recovered by Baltimore at the 12. Suggs had two sacks.

Pass interference and holding penalties extended an 18-play drive that lasted 9:38 for the Ravens. Tucker converted from 25 yards out to make the score 20-0 late in the third quarter.

"We've got 15 games left," Suggs said. "We did some good things today. It was a good place to start."

NOTES: Bengals RG Trey Hopkins, one of three new starters on the offensive line, suffered a left knee injury in the second quarter and did not return. T.J. Johnson replaced him. ... Baltimore, coming off an injury-riddled offseason, lost two key players when LB Za'Darius Smith (knee sprain) and RB Danny Woodhead (hamstring) left with injuries in the first half. ... Bengals first-round draft choice WR John Ross was inactive due to a knee sprain. ... Bengals LB Vontaze Burfict and CB Adam Jones were suspended for Sunday's game. ... Baltimore now leads the all-time series 22-21. Cincinnati has won six of the eight meetings, but Sunday's loss snapped a five-game winning streak over the Ravens at Paul Brown Stadium.