SANTA CLARA, Calif. — Although Mike Nolan knows every loss must be publicly labeled a disaster in the all-or-nothing football world, the 49ers coach has lost more than enough games in his NFL career to see the difference between a good defeat and a bad one.

Nolan actually thinks San Francisco's season-opening 23-13 loss to the Arizona Cardinals was not only one of those good losses, but a result that makes him feel a whole lot better than the two shaky victories with which his club opened last season.

"We're going to be a better football team than we were last year," Nolan said Monday. "I believe we already are. (Although) we're 0-1, we were 2-0 last year, but we had our issues. I'm excited about the prospects on this football team, but it is about winning, so it's difficult to get too excited when you're 0-1."

Last year, San Francisco improbably grabbed last-minute wins over Arizona and St. Louis in two poorly played games that foreshadowed its 5-11 record. Sunday's loss to the Cardinals was much more encouraging on both sides of the ball, even if it puts Nolan in an early hole at the start of what's likely to be his make-or-break season in San Francisco.

The 49ers' 291 yards of offense were more than they produced in all but two games last season, and San Francisco outgained Arizona (285 yards) despite having the ball for less than 23 minutes. The Niners' defense limited the Cardinals to 4.4 yards per play and stopped them on 11 of 16 third downs.

San Francisco committed five turnovers, yet only one of them — linebacker Takeo Spikes' fumble on a clever pooch kickoff — led to points for the Cardinals. Though quarterback J.T. O'Sullivan castigated himself for his two fumbles and an interception in his first NFL start, both fumbles were almost unpreventable under the circumstances, and the interception came on a bold throw that nearly worked.

"There's just certain things in football that you can't do," O'Sullivan said. "One little thing here or there, and it doesn't give you the best chance to win."

San Francisco's errors were obvious, from its turnovers to the defense's inability to stop the Cardinals' succession of clock-killing drives in the second half. The Niners had the ball just once in the first 28 minutes of the second half, losing any chance to stay close.

"We only had the ball for two possessions in the second half, and we've got to do a better job of making those possessions count," center Eric Heitmann said. "We were able to move the ball better than last year, but it's still not good enough."

Nolan didn't have any new information on backup quarterback Alex Smith's shoulder injury, which kept Smith out of Sunday's lineup and might end his career in San Francisco. The former No. 1 draft pick didn't get any new information Monday from Dr. James Andrews, who performed surgery on his right shoulder last December to repair three torn ligaments.

Smith is waiting for Andrews to evaluate the injury on film before the 49ers decide whether the broken bone in his shoulder requires surgery, which could keep him out for the season. If Smith isn't the starting quarterback heading into next season, the 49ers almost certainly will cut a player due to make $9 million in base salary in 2009.

Smith said the injury, a probable stress fracture which he first noticed during last Friday's practice, left him in "pretty severe" pain.

"It was really hard just to be out of uniform again," Smith said. "I went through that last year. I'm tired of being in a warmup uniform."

The 49ers are evaluating several veteran backups to replace Smith behind O'Sullivan and Shaun Hill. Jamie Martin, a longtime Rams quarterback under Niners offensive coordinator Mike Martz, is available after the Saints let him go in the last offseason.