Raiders postgame thoughts

Posted by ESPN.com's Bill Williamson

SAN FRANCISCO -- Random post-game thoughts from Oakland where the Raiders lost to the 49ers, 21-20:

The Raiders need to work on their run defense, which was ranked 31st in the NFL last year. San Francisco had 275 yards rushing. If Oakland doesn't fix its problems in this area, it will be gutted defensively and have difficulty staying in games. It's simple: if you can't stop the run, it is very difficult to win in the NFL.

Oakland coach Tom Cable said the Raiders need to work on the fundamentals of tackling better. Added star cornerback Nnamdi Asomugha: "It was disappointing because we've really worked on it. It's something that we clearly need to continue working on."

Oakland's backup defensive backs struggled in the second half and the 49ers' passing game clicked.

Oakland quarterbacks Bruce Gradkowski and Charlie Frye both played decently for the second straight game as they fight for the No. 3 job. Backup quarterback Jeff Garcia, who didn't play last week, was intercepted in his only series. Garcia will need to get more work in the final two preseason games.

Running back Justin Fargas (hamstring) and Asomugha (heel) departed the game early. Neither injury is expected to be serious.

Oakland rookie tight end Brandon Myers looked sharp in the passing game. He could be a decent backup for Zach Miller. Myers was drafted because of his blocking but he had four catches for 75 yards.

Rookie receiver/returner Nick Miller's chances of making the 53-man roster may have taken a slight hit with a fumbled punt in the fourth quarter.

Oakland had seven penalties and now has 21 penalties in two preseason games.