PITTSBURGH -- The Miami Dolphins' defense struggled mightily down the stretch in the regular season, and it didn’t hold up well early in Sunday’s playoff game against the Steelers.

The Pittsburgh Steelers' high-powered offense has shredded Miami’s defense early in the first half en route to a 20-6 lead at intermission. Pittsburgh gained 219 total yards in the first quarter alone and 287 yards total in the first half.

Antonio Brown had four catches for 125 yards and two TDs in the first half on Sunday. Rob Carr/Getty Images

Miami had no answers early for Steelers Pro Bowl receiver Antonio Brown. The Dolphins are missing their No. 1 cornerback Bryon Maxwell due to an ankle injury, and Brown took advantage of a pair of one-on-one matchups with Dolphins corner Tony Lippett. Brown turned a screen play into a 50-yard touchdown and a slant into a 62-yard score.

Brown was held to just four receptions for 39 yards in Miami’s regular-season win over Pittsburgh. But Sunday, Brown already has four catches for 125 yards and two touchdowns.

Miami’s defensive line, its strongest unit, wasn’t getting much push at the line of scrimmage. This is a group led by two Pro Bowlers in defensive tackle Ndamukong Suh and defensive end Cameron Wake. Both have been quiet in the first half as Steelers running back Le’Veon Bell was patient and picked his holes. Bell has 99 yards rushing and a touchdown on 17 carries.

The performance so far looks similar to the Dolphins' recent defensive struggles. Miami’s defense allowed 985 yards and 66 total points in the previous two weeks against the New England Patriots and Buffalo Bills.