On Rams sniffing out 49ers' play tendencies

San Francisco 49ers safety Craig Dahl says his former team, the St. Louis Rams, played the 49ers tough last season in part because they sniffed out run-pass tendencies through personnel giveaways.

2012 49ers Offensive EPA by Opponent

Dahl alerted 49ers coaches, who were already aware of the problem, Dahl told reporters from the 49ers' mandatory minicamp.

On the surface, I don't see why Dahl would reveal that information publicly if there were any chance the Rams would rely upon the same tendencies for even a brief moment during matchups scheduled for 2013. Of course, with Dahl playing for the 49ers, the Rams had to figure inside information would get to San Francisco coaches anyway. They had to figure 49ers coaches would change up tendencies from previous matchups regardless.

The Rams posted a 1-0-1 record against the 49ers. Their defense held the 49ers to one touchdown pass across two games. The Rams held the 49ers to their fourth-lowest Total QBR score of the season (43.4) during a 24-24 tie at Candlestick Park in Week 10. They pressured 49ers quarterback Colin Kaepernick into a critical turnover during a 16-13 Rams victory in Week 13.

While the 49ers made some big plays against the Rams, including Kaepernick's critical 50-yard scramble in Week 13, San Francisco finished those 2012 games against St. Louis with a negative total for offensive expected points added, as the chart shows. The single-game figures were plus-8.1 in Week 10 and minus-8.9 in Week 13.

Dahl's comments mark the second time since joining the 49ers that he has made significant comments regarding an NFC West opponent. He followed news of Seattle Seahawks defensive end Bruce Irvin's suspension by saying he had "no sympathy for violators" of NFL drug tests. Dahl and 49ers coach Jim Harbaugh are on the same page there.

I'm at Rams camp this week, but there was no practice Wednesday. I'll follow up on this one no later than Thursday.

Update: Nice work by @T_Bron for recalling the @NinersNation piece suggesting the Rams' linebackers had the 49ers' tendencies sniffed out.