Despite the many positives from the Steelers' win over the Eagles, the defense had a much rougher time in the second half of the game than the first half. This continued a disturbing trend: in three of the four games so far this year, the defense has played respectably well in the first half and then is totally unable to get off the field in the second half. To recap, the Broncos scored on all three of their second-half possessions (not including the final kneel-down to run out the clock). The Raiders scored on all four of their second-half possessions. The Eagles scored on two of their three second-half possessions. In fact, that game would have replicated the two losses had the Steelers not been able to hold the Eagles to a three-and-out on their second possession of the third quarter.
For the stat-heads, here is confirmation of the trend. Over the first four games, the Steelers D has given up 31 points in the first half but 52 points in the second half (not include the Broncos' pick-6, which is on Ben). Excluding the Jets game, during which New York's struggles became increasingly feeble, the split is 21 points / 52 points. Yardage reflects the same trend. Excluding the Jets game, the defense has yielded an average of 122 yards in the first half and 201 in the second half. In other words, the Steelers play like the best defense in the league in the first half but one of the worst in the second half.
So what is wrong? The obvious explanation is that there are too many old guys and they are getting tired in the second half. The team has enough depth to rotate on the D-line, however, and two of the old guys, Polamalu and Harrison, have hardly played. Or maybe the opponents are making better adjustments at halftime. I hope someone more knowledgable than I can explain this strange phenomenon. I also hope the coaches can figure out how to correct it.