"He's going to play a lot better," Harbaugh said during his Monday news conference. "I guarantee you that."
Why is Harbaugh so confident that Flacco will bounce back?
"He always has. He's always bounced back," Harbaugh said. "He bounced back from a tough first half and led us on that drive to start the second half. It's the kind of person he is. He's a competitive guy. He's a talented guy. He's starting his third year. You look around and look at the history, there are going to be ups and downs."
Harbaugh is right -- Flacco's history suggests he'll rebound mightily Sunday against the Cleveland Browns.
Flacco has thrown three interceptions twice in the regular season, and both times he came back to record a quarterback rating of more than 120.0 the next game.
In 2008, he threw three picks at Indianapolis. Then, at Miami, he completed 17 of 23passes for 232 yards. He had one touchdown pass and no interceptions for a 120.2rating.
In 2009, Flacco was intercepted three times at Green Bay. Then, against the Detroit Lions, he connected on 13 of 20 throws for 230 yards. He had one touchdown pass and no interceptions for a 120.8 rating.
One of the reasons Flacco is able to overcome adversity is his even-keel demeanor. There was no sign of panic from him even after ending a game with interceptions on his final two drives.
"You just move on," Flacco said. "You have to take it game by game. I don't think anyone feels good about it. We just have to make sure we bounce back and get ready to go. I think everyone will."
There were expectations that this would become Flacco's breakout season. He has already won three playoff games, and he threw for the fifth-most passing yards by a quarterback in his first two seasons (6,584).
But his lackluster play in the first two weeks of the season -- he has completed 48percent of his passes for 402 yards, one touchdown and five interceptions -- has created some major concern within the Ravens' fan base.
But fans aren't the only ones who have shown little patience this season. NFL coaches have already benched six starting quarterbacks in a game this season (Buffalo's Trent Edwards, Carolina's Matt Moore, Jacksonville's David Garrard, Arizona's Derek Anderson, Oakland's Jason Campbell and Tennessee's Vince Young).
Harbaugh declined to say whether there were discussions Sunday about benching Flacco for $3.8 million backup Marc Bulger during the Bengals game.
"I probably wouldn't share that with you if there was," Harbaugh said.
"That's kind of what we talk about in-house. You always want to put your team in the best position to win a football game on a given day."
Flacco's play has been costing the Ravens this season because his turnovers are piling up at an alarming rate.
He has turned the ball over six times (five interceptions and one fumble) in two games. Flacco didn't commit his sixth turnover last season until the eighth game.
His five interceptions are most in the NFL. Five quarterbacks have thrown four.
"It's just not the quarterback," Harbaugh said. But "Joe will be the first one to tell you that he has to play better."
Flacco isn't the only one to blame for the frustrating lack of production.
The offensive line allowed Flacco to get hit eight times at Cincinnati. The wide receivers didn't get consistently open and dropped passes. That's why Flacco had more yards scrambling (10) than passing (6) in the first four drives Sunday.
According to a team source, these struggles prompted Boldin to have a fiery talk with his offensive teammates at halftime Sunday.
"We need to find that rhythm where everybody is touching the ball and keep the defense off balance," tight end Todd Heap said. "You look around the huddle and you see playmakers. It's a matter of going out and executing."
It has been such a dreadful start that wide receiver Mark Clayton, who was traded to the St. Louis Rams, has as many touchdowns (two) as the entire Ravens offense at this point.
"Nobody's got a better perspective on it than us in-house," Harbaugh said. "We like our football team. We like our players. We're not one bit concerned about our talent level at any position."
The early-season slump is surprising. Over the last six games in 2009 (including playoffs), the Ravens averaged 26 points. It looked like the Ravens had hit their stride in Cam Cameron's offensive system.
But the Ravens have managed just 10points in each of the first two games. The offense had been held to 10 points or fewer only five times in the first two seasons (32games) under Cameron.
"Players believe in coaches. Coaches believe in players," center Matt Birk said. "We've got players who believe in each other. We'll work to get better. There's no secret thing. You can't say, well, let's not turn the ball over or let's score more points. It's not quite that easy. But it is easy enough to focus on working. And we'll work hard to get this worked out."
The Ravens' offense is ranked 24th in total yards and is in the bottom five in scoring.
"It's going to materialize," Harbaugh said. "We're going to be a winning offense, there's no doubt about that."