The cashier took one look at my T-shirt the other day and offered a suggestion.

If that shirt said ‘Seahawks’ on it, it’d be a much better shirt, he said, or at least he uttered words to that effect.

I don’t even remember exactly where I was — I think it might have been a truck stop in Ellensburg, Wash., while we were making a quickie trip to western Washington and back.

I do remember hearing something come over the loudspeaker telling customer No. 47 that his shower was ready. But I didn’t even know what the cashier was talking about until I looked down and remembered I was wearing a 49ers T-shirt.

It did get me to thinking a little bit later — do Seahawk fans consider the 49ers their rivals in the NFC West? I understand they’ve been in the same division since 2002, but it seems to me to have a rivalry, it would help if both teams were good — preferably at the same time.

And that hasn’t been the case with the Seahawks and the 49ers.

WHEN THE Seahawks were really good a few years back, the 49ers really weren’t. And when the 49ers were good, well, that was probably back when Steve Young and then Jeff Garcia were the quarterbacks, and the Seahawks were still back in the AFC West.

The Seahawks and St. Louis Rams were rivals a few years ago, with the Rams once winning a wild-card playoff game in Seattle. But the Rams have been miserable in recent years.

The Arizona Cardinals became the top team in the division the past couple of years, but with Kurt Warner now gone at quarterback, teams like the Seahawks and 49ers are looking to seize the moment.

Seattle’s downfall in recent years could be excused somewhat by injuries. If the Seahawks can stay healthy and stop acquiring washed-up running backs, new coach Pete Carroll’s “Kumbaya” approach might work.

San Francisco, meanwhile, is hoping it has hired some offensive linemen to actually protect the quarterback. If that’s the case, the onus is on quarterback Alex Smith to throw the ball to his own receivers — provided, of course, they can find a way to get open, which is something that has been easier said than done in recent seasons.

NFL SEASON openers always attract a generous amount of attention. And that could be especially true in the Pacific Northwest this year, when Seattle plays host to San Francisco on Sunday, Sept. 12 at Qwest Field.

And, if both teams live up to their fans’ expectations, the second meeting of the season — on Week 14 in San Francisco on Dec. 12 — could be for the division lead.

If that happens, then it really will matter what kind of T-shirt you wear when visiting western Washington.

Mark Nelke is sports editor of The Press. He can be reached at 664-8176, Ext. 2019, or via e-mail at mnelke@cdapress.com.