Sweet matchup between bitter West rivals

Alex Smith is completing 69.5 percent of his passes with four touchdowns and one interception when opponents come after him with five or more pass-rushers.

That note, delivered from ESPN Stats & Information, stands as a positive indicator for the San Francisco 49ers as they prepare to face Arizona on "Monday Night Football" in Week 8.

That is only part of the picture, however.

The Cardinals are allowing a league-low 40.9 percent completion rate on these plays featuring added pressure. As the chart shows, Arizona's blitz packages gave Smith problems last season. Smith posted a 9.5 QBR score out of 100 on these plays against Arizona. That compares to 80.4 against the 49ers' first seven opponents this season.

The 49ers arguably have not faced a defense as good as Arizona's this season. I say "arguably" because I do expect arguments to break out over this in the comments section.

The Cardinals sacked Smith five times and held him to 4.7 yards per pass attempt during their Week 14 home victory over the 49ers last season. They have yet to allow more than 21 points in a game this season despite frequently getting little help from their offense. Arizona ranks third behind Chicago and Houston in ESPN's expected-points metric, which trumps traditional yardage-based measures for reasons explained here.

We can all agree on this: Arizona's defense leads the league in publicly disclosed disdain for the 49ers.

"I really felt like I could have had four sacks last week and I had zero," Cardinals defensive lineman Calais Campbell told Sirius radio (via Matt Barrows). "So I gotta make up for that this week especially going against the 49ers who I really hate with a passion. I can't wait to go out there and stick it to them. Alex Smith I've gotten down a few times so I know he's thinking about me a little bit. So I can't wait to get out there ..."

Campell's teammates, Darnell Dockett and Adrian Wilson, have usually been the ones to speak out against the 49ers.

Perhaps the Cardinals have not yet dived into the video showing the 49ers' offensive line dominating opponents this season. Ben Stockwell of Pro Football Focus took note after watching San Francisco run the ball consistently well against Seattle.

"Each starter on the Seahawks’ defensive line recorded the lowest single-game run defense grade ever earned individually in the five years we have been grading games here at Pro Football Focus," Stockwell wrote. "This was dominance that we have simply never seen imposed on this Seahawks defense before."

Earlier: Gore, Cardinals on collision course