When the Ravens last traveled to Heinz Field, Pittsburgh Steelers quarterback Ben Roethlisberger's six-touchdown performance set off an overhaul of the defensive backfield that only recently ended.
The secondary that carried the Ravens into the playoffs has played well lately, only allowing an average of 173 passing yards per game in the last four games of the regular season.
But Saturday, the unit will face its sternest test yet in Roethlisberger, who in that Nov. 2 start exemplified the type of quarterback the Ravens have struggled to defend recently.
In six games this season against the quarterbacks among the NFL's top eight in passing yards — Roethlisberger twice, plus Atlanta's Matt Ryan, Indianapolis' Andrew Luck, New Orleans' Drew Brees, and San Diego's Philip Rivers — the Ravens allowed an average of 316.7 passing yards per game with 14 touchdowns and a 68.9 percent completion rate, for a 100.3 quarterback rating.
In the other 10, the Ravens gave up an average of less than a touchdown per game, with 244 yards allowed per game and an 83.2 quarterback rating.
Ravens defensive coordinator Dean Pees said a high caliber of quarterback is the only thing his defense will see for the rest of the season, and he'll help them prepare for that.
"I think they're ready," Pees said. "I think it's going to be a big challenge. It's that time of the year where everybody you're going to play, there's nobody that's not good. Everybody that's in this tournament is good."
By that standard, the Ravens' postseason run will face, almost exclusively, the quality of quarterback that has tormented them all season.
Through the first seven weeks of the season, with games against Roethlisberger, Luck, and Ryan, the Ravens saw their most success against passers who ended up among the league's best, thanks in part to the Pro Bowl-caliber play of cornerback Jimmy Smith.
The Ravens were searching for consistency at cornerback opposite Smith at that point, but they allowed just a touchdown per game and just more than 250 yards per game with the 2011 first-round pick limiting each opponent's top wide receiver.
Then, with Smith and Asa Jackson out, and Lardarius Webb still searching for his top form, the Ravens' problems against top quarterbacks were magnified.
Roethlisberger threw for 340 yards and six touchdowns in Week 9, Brees had 420 yards and three touchdowns in a Monday Night Football game three weeks later, and then Rivers had 383 yards and three touchdowns in Week 13.
After the Pittsburgh game, the Ravens cut cornerbacks Chykie Brown and Dominique Franks. Journeyman Danny Gorrer and converted safety Anthony Levine saw time at cornerback in the games against New Orleans and San Diego.
Overall, seven different cornerbacks started for the Ravens, with safety Matt Elam also playing a nickel cornerback role for most of the year. The Ravens have started nine different defensive backfields in 17 games this season, though they finished the season with a lineup that gives the team confidence.
"I feel really good about the way they're playing back there," coach John Harbaugh said. "They're playing good technique; we're playing better together. We still are chasing perfection."
The Ravens entered Week 14 against the Miami Dolphins with the league's 31st-ranked pass defense, and in that game, they saw the beginning of a four-game upswing.
Opponents hadn't gained fewer than 889 total passing yards in any four-game stretch against the Ravens this season to that point. In the final four games of the season, the Dolphins, Jacksonville Jaguars, Houston Texans, and Cleveland Browns combined for just 692 passing yards.
Miami's Ryan Tannehill was the best quarterback the Ravens faced in that span, and finished 11th in the league with 4,045 yards. The other three quarterbacks — Jacksonville's Blake Bortles, Houston's Case Keenum and Cleveland's Connor Shaw — have a combined 24 career starts and five victories.
On the Ravens' side, however, the success is partially due to finding some stability in the secondary. Webb, who missed several weeks in training camp, is playing his best football of the season.
Across from him, the Ravens have found a solution in former practice squad cornerback Rashaan Melvin, who was signed off the Dolphins' practice squad to fill one of the roster spots opened by the post-Pittsburgh purge in Week 10.
As a second-year pro in his first stint on an active roster, Melvin's attention to his own game has prevented him from thinking about the quality of quarterback he has faced this year or the one that looms Saturday.
"Me being a young guy, I really don't focus too much on the quarterback," Melvin said. "I focus on my details, my keys that I need to focus on. There are a lot of good quarterbacks around the league.
"They wouldn't be at this level if they wasn't good players, so I don't really feed into the quarterback, who the quarterback is."
Pees said the continuity since Melvin stepped in against Jacksonville has helped the unit.
"The good thing is at least we've had a little continuity here the last couple weeks with the secondary, the verbiage, the communication, all that kind of stuff is starting to get better each week," he said.
Despite the recent success, Webb says the group is still rounding into form.
"I think we're still getting there," Webb said. "I don't think we have yet. We haven't proved anything yet. We've still got work to do. We've got to still keep stepping up all game if we want to go far in these playoffs.
"It's just my responsibility to have them boys ready, and I'll have them ready."