The best NFL quarterbacks are good against standard and added pressure alike.
Aaron Rodgers comes to mind. The Green Bay Packers' quarterback leads the NFL in Total QBR when opponents send four or fewer pass-rushers, and also when they send five or more, according to ESPN Stats & Information.
TD-INT by Opposing Pass-Rushers
Alex Smith's stronger production against five or more pass-rushers has stood out all season.
Smith vs. four or fewer rushers: six touchdowns, four interceptions and 16 sacks in 222 dropbacks, with a 47.7 QBR (50 is average) and an 84.7 NFL passer rating.
Smith vs. five or more: seven touchdowns, one interception and 14 sacks in 106 dropbacks, with a 57.2 QBR and 105.9 NFL rating.
Multiple factors can produce such a disparity. A quick-thinking quarterback armed with a strong game plan and a solid protection scheme can have an advantage against added pressure. Quarterbacks working behind weaker offensive lines could suffer against standard pressure if opponents got to them without sacrificing coverage. Having additional players in coverage affords defenses with additional combinations in coverage, another consideration.
The chart immediately below ranks quarterbacks by the largest QBR disparity when facing five or more pass-rushers vs. four or fewer. Smith and Arizona's Kevin Kolb are among 11 quarterbacks with higher QBR scores against five or more rushers. They have done better against pressure, in theory. Ranking higher on the list isn't necessarily desirable; like Rodgers, a top quarterback should produce in both areas.
Fifty is an average score, with 100 as the limit.
QBR differential is an imperfect measure because point differentials nearer the margins (zero and 100) carry more significance than they do nearer the middle of the range. But the disparities are still helpful in showing how quarterbacks perform, in general, across these situations.
Rex Grossman, who heads the first chart, completed 9 of 12 passes for 117 yards and one touchdown with no interceptions and one sack when the Seahawks sent five or more rushers against him Sunday. He completed 17 of 23 passes for 197 yards with one touchdown, two interceptions and no sacks against standard pressure.
2011 Total QBR: Higher vs. 5+ Pass-rushers
The final chart shows the 22 qualifying quarterbacks with better QBR numbers when facing four or fewer pass-rushers, again ranked by percentage difference.