In his fifth season as a starter, Flacco has been occasionally erratic and inconsistent.
Flacco has passed for 3,220 yards on 60 percent accuracy, generating 18 touchdown passes and nine interceptions for an 87.1 quarterback rating.
With Cameron gone, obviously the focus will turn toward Flacco and how he fares with a new offensive coordinator in Caldwell.
"What I've been seeing from him is consistently getting better," Mason said of his former quarterback. "At times, he's been missing, which you can't have from your quarterback. I've also seen him play tremendously this year. Especially with them changing offensive coordinators, everybody will say, 'What we thought was the problem is gone, the so-called anchor holding us down.' If we continue to flutter, is it then on Caldwell or on Joe as a quarterback?
"Joe needs to be cognizant that the pressure is on him now. No one else can say on that team or in the media or the fans that it was Cam's fault going forward. If the problems continue, then it's bigger than the offensive coordinator. I think Joe will continue to do a good job. If he doesn't, it will be shocking to me. If he doesn't take the opportunity to take a stranglehold of this team from a leadership standpoint, I'll be very surprised."
After accepting the new responsibilities, Caldwell met with the offensive coaches, watching video of the Ravens' 31-28 overtime loss to the Washington Redskins that marked Cameron's final game as offensive coordinator. He also met with players.
"I had an opportunity to talk with them and really, in a nutshell, just try to make them understand really what we're trying to do is just to get about that much better," said Caldwell while holding his index finger and thumb a few inches apart. "And that's a difficult task obviously trying to get that done in this league, but that's what we're shooting for."
Harbaugh didn't say whether Caldwell will be the Ravens' permanent offensive coordinator, but did indicate that he would work in a dual capacity by remaining the quarterbacks coach. It's also unclear if Caldwell will shift to the field as offensive coordinator or remain in the coaches' booth as he did as quarterbacks coach.
When asked if this represented an audition for Caldwell, Harbaugh replied: "Long-term considerations are long-term considerations, and that's not in the forefront of our mind right now."
Jim Caldwell File
Hometown: Beloit, Wis.
Resume: Former Indianapolis Colts head coach and quarterbacks coach where he coached quarterback Peyton Manning, now with the Denver Broncos.
*Hasn't been an offensive coordinator in NFL, coaching quarterbacks with the Tampa Bay Buccaneers prior to joining the Colts in 2002.
*Was Manning's position coach in 2004 when he threw 49 touchdowns and was named NFL Most Valuable Player.
*Caldwell was the head coach at Wake Forest from 1993 to 2000 and was previously the quarterbacks coach/passing game coordinator at Penn State when Kerry Collins was the Nittany Lions' quarterback.
*Other coaching stints include time at Louisville, Colorado, Northwestern, Southern Illinois and Iowa.
*Was a four-year starting defensive back for the Iowa Hawkeyes.
Personal: Married to Cheryl and has three sons, Jimmy, Jermaine and Jared and one daughter, Natalie.
-- Aaron Wilson