There's a smashmouth aspect to a Green Bay Packers offense largely defined by star quarterback Aaron Rodgers and a deep group of receivers that includes Jordy Nelson, Randall Cobb and James Jones.
Rookie running back Eddie Lacy provides a tackle-breaking presence, a change of pace to all the passing.
The 5-foot-11, 230-pound second-round draft pick rushed for a career-high 99 yards on 23 carries in a win against the Detroit Lions last week.
The Packers have upgraded their running game in 2013, ranking fifth in the NFL with 141 rushing yards per game.
Ravens defensive coordinator Dean Pees compared Lacy to Indianapolis Colts running back Trent Richardson, a fellow former Alabama standout.
"There are similarities in the fact that they're both downhill runners, strong, can carry the pile and break tackles," Pees said. "He's not a scat-back-type guy. He's a hard-nosed, Alabama running back who can hit you downhill. So he's added a lot that way, because I think sometimes what happens, especially when you play Green Bay, [is] they're spread out a lot, they're going to throw the ball a lot, and they've got great, talented receivers and tight ends.
"So, all of a sudden, you get a little spread out, and then in the running game, you need a back who can break tackles. You don't necessarily need the quick guy who can get the edge, because you're kind of spread out on defense most of the time, anyhow. If a guy can get downhill and break tackles, that's the kind of back you need."
The Packers are depending on Lacy to complement Rodgers. His 150 rushing yards rank second in the NFL among rookie running backs, even though he's played in just three games because of a concussion.
"Lacy is a powerful guy," Ravens coach John Harbaugh said. "He can run. More of a north-south hard runner, though."
Last season, the Packers were 20th in the NFL with 106.4 rushing yards per game.
Now they have Lacy and shifty running back Johnathan Franklin, a fellow rookie out of UCLA, as James Starks recovers from a knee injury.
Lacy is a focal point for the Packers' offense, and a point of emphasis for the Ravens. That includes strong-side linebacker Courtney Upshaw, Lacy's former college teammate.
"It's football, man. We're on opposite teams," Upshaw said. "We're both going to play to the best of our ability and help our teams get a win. Eddie Lacy is my boy, but it's football." (Benny Sieu / USA TODAY Sports)
As the Ravens (3-2) prepare for the Green Bay Packers (2-2) on Sunday at M&T Bank Stadium, here's Baltimore Sun reporter Aaron Wilson's checklist of key areas and players to keep an eye on.