Alex Smith has right read on Philly defense

Alex Smith was absolutely correct Wednesday when describing fundamental changes to the Philadelphia Eagles defense he'll face Sunday.

Last season, Smith and the San Francisco 49ers prepared for an Eagles defense that rushed the passer with five-plus defenders 14.8 times per game by season's end. That figure ranked fifth in the league, according to ESPN Stats & Information. The 2011 Eagles, more confident in their secondary with new cornerbacks Nnamdi Asomugha and Dominique Rodgers-Cromartie, are sending five or more rushers 7.7 times per game. That figure ranks 28th.

2010-11 Eagles vs. the Pass

"Yeah, very different from the Eagles from the past," Smith told reporters in Ohio, where the 49ers are staying between games in the Eastern time zone. "There is much less pressure in terms of linebackers and secondary. Before it was high pressure, a lot of different looks, giving me a lot of different things to think about. This isn’t quite as much variety, but they’re still giving as much pressure. I think they lead the NFL in sacks."

The Eagles did rank first in sacks with 12 until the Dallas Cowboys inched past them by one during their Monday night game against Washington. Improved coverage from in the secondary should, in theory, give the Eagles' front four more time to reach opposing passers unassisted. Why blitz at the expense of coverage when the front four has time to get pressure?

2011 Alex Smith vs. the Rush

The 2010 Eagles rushed the passer with at least one defensive back 7.6 times per game on average, eighth-most in the league. The average is twice per game this season. Only Jacksonville, Detroit and Cleveland have sent DB pressure less frequently.

OK, then. Next question: How has Smith fared when teams rush four or fewer defenders relative to when they send more? And what about when teams send DB pressure?

So far this season, Smith ranks 21st in NFL passer rating (81.2) and 25th in Total QBR (43.7) against four or fewer rushers. His NFL rating is 115.0 with an 80.1 QBR against five or more.

Smith is a sensational 8 of 8 passing for 106 yards, one touchdown and perfect ratings -- both NFL and QBR -- when teams rush at least one defensive back this season. But the Eagles have pressured with their secondary only six times through their first three games, so Smith might have few opportunities to build on his fast start in those situations.

The Eagles' change in approach would appear to work against Smith overall.