The voices of Joe Flacco and Dean Pees were audible from a football field away — Flacco barking out line calls and Pees providing instruction and encouragement to his young defense.
Wearing all black on a steamy Baltimore afternoon, Caldwell sporadically looked down at his play sheet but quickly returned his gaze to the action in front of him. When he spoke, he did so in measured tones, opting more for individual conversations than loud lectures.
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"The one thing, he's always calm, cool and collected and smooth in the way he talks to us in the meeting room and how it relates on the field," Ravens tight end Ed Dickson said. "You can see the results."
When he replaced Cam Cameron as the Ravens' play caller last December — a move many Ravens credited as a big factor in the team's Super Bowl run — Caldwell was adamant that the team's offensive philosophy would not change.
There were only three regular-season games remaining, so even if Caldwell felt the need for it — and he clearly didn't — there wasn't enough time to implement such a drastic shift anyway.
But after spending significant time this offseason studying the Ravens' offense, Caldwell acknowledged that the team's attack could feature a few changes and his imprint could be more noticeable.
"It's different because, obviously, right at the beginning of the offseason, we had a chance to sit down and look at everything that we're doing [and] make the adjustments that we think we need to make," Caldwell said Friday after the Ravens finished up the second of three weeks of organized team activities. "Really, there aren't that many, for the most part, but we are changing a few things here and there, adding a few wrinkles, so it's been good. This is a little bit different than when I took over in December because we've had an opportunity to kind of think through a lot of things."
Caldwell was predictably vague about any specific changes. No NFL head coach or coordinator is going to unveil those plans through the media, especially not two months before training camp is even scheduled to begin and three months before the regular-season opener.
Still, Caldwell clearly recognizes the need for offensive improvement, despite the Ravens averaging 410.3 yards of total offense and 31 points per game in the playoffs on their way to the Super Bowl title and Flacco having one of the best postseasons for a quarterback in league history with 11 touchdowns and no interceptions.
"The big thing is we're just trying to get better in every phase," Caldwell said. "We averaged a little over 4 yards a carry just in terms of the running game. In certain situations, first and second down, we want to be a bit better. We want to be more consistent in terms of our passing game. We have that big-play capability, but we also need to be really precise in terms of our deep passing game. So we're working on a little bit of everything."
While the Ravens defense was overhauled this offseason, Caldwell's offense returns mostly intact. The only piece missing from last year — and it's a big piece — is veteran wide receiver Anquan Boldin, who was traded to the San Francisco 49ers. Caldwell called Boldin a "void" but repeatedly praised the team's younger receivers and some of the playmakers at other positions.
Versatile rookie fullback Kyle Juszczyk, a fifth-round pick from Harvard, was added to the mix and he could provide a different dimension.
But overall, the Ravens didn't think much offensive change was necessary, not with Flacco enjoying a breakout season, not with so many of their younger players, like wide receiver Torrey Smith, tight end Dennis Pitta and running back Bernard Pierce, coming into their own, and not with Caldwell growing more comfortable in his new role by the day.
"If it ain't broke, don't fix it," said wide receiver-return specialist Jacoby Jones, who will see an increase in offensive snaps with Boldin gone.
It's not that Caldwell, who called plays for the first time in the NFL in the Ravens' Week 14 loss to the Denver Broncos, inherited a bad offense. At the time of his dismissal, which came during his fifth season with the Ravens, Cameron's group ranked ninth in the NFL in points per game (25.5) and 18th in yards per game (344.4).
But the offense was still too inconsistent.
Pro Bowl running back Ray Rice disappeared from the game plan too many times, and the players — mainly Flacco — never felt they had enough say in what the Ravens were doing on game day.
However, under Caldwell, who was hired as the team's quarterbacks coach in January 2012, the Ravens ran the ball more. Flacco moved out of the pocket more frequently, threw more deep passes and wasn't as hesitant to use the middle of the field.
The results were immediate. In the final seven games, including the playoffs, the Ravens averaged 400.6 yards per game and 27.3 points per game. Several of the Ravens' top offensive players believe that was just a start of things to come.
"We're going to continue to get better on offense, and I think Jim is a great leader for our offense," Pitta said. "He's efficient, he's detailed. Everybody knows what is expected of them, the standard that is expected. So that's the great thing about it. You come onto the field and you have to try to meet that standard. I'm excited about our potential offensively with Jim at the helm and the talent that we have. It should be a good year."
Said Smith: "I think obviously we're confident in it. It's our second year with him. It's the same offense for us, some minor tweaks in the way he calls it. We're all excited about it. I don't think there's a better teacher in the league as an offensive coordinator. We're definitely lucky to have him."
As he surveyed his offense Friday, Caldwell, 58, was wearing sweatpants, a long-sleeved workout shirt and a Ravens' hat. Still, when he spoke, he sounded more like a reassuring professor than a hard-to-please football coach.
Caldwell certainly understands the expectations of the offense for the coming season. Just don't expect his demeanor to change too much, nor the accountability that he'll demand.
"Your responsibility changes a little bit," he said. "There are certain things you are responsible for, so you have to take care of those, but in terms of overall change in demeanor, or anything of that nature, no. There's not a whole lot of change there. But just in terms of getting done what we need to get done, that's my job. When they don't get it done right, guys lose their job, right? So we have to get it done right."
Baltimore Sun reporters Aaron Wilson and Matt Vensel contributed to this article.