The Ravens offensive line was offensive in its first game of the season, and head coach John Harbaugh wants to see improvement quickly.

Quarterback Joe Flacco was under duress all afternoon in Denver on Sunday, as he was pressured on 22 of 34 of his dropbacks, sporting an average time to throw of just 2.49 seconds, according to Pro Football Focus. The site ranked the Ravens' line dead last in pass-block efficiency, anchored down by tackles Rick Wagner (-6.4) and James Hurst (-10.6). Hurst was filling in for Eugene Monroe, who suffered a concussion on the opening drive.

While top-notch pass rushers like Von Miller and DeMarcus Ware car wreak havoc on any offense, Harbaugh didn't like what he saw on film.

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"Our tackles, they've got to do a better job," Harbaugh said via the team's official site. "They've got to set square and they've got to punch on time. When they do that, they'll do well against anybody. When you don't do that, you're not going to do well against anybody. That was an issue for us over the course of the game."

Harbaugh also said that his coaches didn't do a good enough job helping Wagner and Hurst with extra blockers once it was evident they were struggling to combat Denver's rush.

Guard Kelechi Osemele, who received a -4.1 from Pro Football Focus, said the line wasn't able to establish chemistry in the preseason due to various injuries.

"First-game jitters, emotions all over the place," Osemele said. "It just took us a while to get things under control and play with technique and play as a unit. I didn't play in many preseason games and we just had guys that were banged up through camp. I think as the season progresses, we'll start faster."

Flacco finished the game just 18 of 32 for a paltry 117 yards and two interceptions. He'll look for more production this Sunday in Oakland.

h/t: Baltimore Ravens