Ben Roethlisberger and the Steelers are 0-1. (US Presswire)

Ben Roethlisberger lost the duel between three-step drop-back quarterbacks and the Steelers defense -- missing former Defensive Player of the Year James Harrison (knee) and S Ryan Clark (sickle cell trait) -- couldn't hold a second-half lead in a 31-19 loss to the Denver Broncos.

It wasn't as awful as the 35-7 season-opening rout to the Baltimore Ravens last year. But it wasn't what the Pittsburgh expected, either.

Offense: C -- The Steelers dominated the game in the second and third quarter, with Big Ben and Co. holding the ball for 20 minutes in one stretch while the Broncos only had three offensive plays. Too bad time doesn't translate into points on the scoreboard. Field goals don't help much, either. Same as too much of last season, the Steelers showed an inability to collect TDs in the red zone.

Defense: C -- Harrison and Clark were noticeably absent. The Steelers played at least a half-dozen backups on defense to try to rest the starters because of the mid-80s heat and high altitude in Denver. Still, the defense couldn't clamp down the Broncos' running game. And Manning, whom they sacked twice in the first half, had nothing but time and clean passing lanes the second half. If S Troy Polamalu plays mostly deep coverage, this defense won't cause as much havoc as in previous years.

Special teams: B -- The less seen of Shaun Suisham field goal attempts, the better for the Steelers. Rookie Drew Butler averaged 47.5 yards per punt in his NFL debut, and dropped a punt perfectly at the Denver 1, an ability he hadn't shown in the preseason. Pro Bowler returner Antonio Brown surprisingly showed up on special teams after word that his increased receiving load would eliminate his return duties. He had two returns for 23 yards. It's smart to keep Brown in the return game because it is another way to get him the ball in the open field.

Follow Steelers reporter Chris Adamski on Twitter @CBSSteelers and @BuzzsawPGH.