On 24th and Castro streets sits a bar called Valley Tavern. This is where I spent my Sunday afternoon Jan. 20.

When I arrived, there were 10 to 20 people waiting outside — squinting through the windows to catch a glimpse of the TVs. After 15 minutes of waiting, I finally stepped into a sea of red and gold regalia. Fans from across the city settled in to watch the San Francisco 49ers play the Atlanta Falcons. The stakes: a trip to Super Bowl XLVII at the Superdome in New Orleans, La.

With that looming, 49er fans sat in agony even as victory seemed all but inevitable. The demeanor of the fans varied from “I don’t believe it” to “I can’t believe it” as the game ended. It had set in that the 49ers were going back to the Super Bowl for the first time in 18 years.

Sunday, Feb. 3, San Francisco will have a chance to do something only three other cities have done in American history: consecutively win a World Series and a Super Bowl. Backtrack to Sunday, Oct. 28, 2012.

I stood on the porch outside my Arballo Drive apartment. I listened to the same frenzied celebration emanate from the surrounding complexes as Sergio Romo struck out American League MVP Miguel Cabrera. The strikeout sealed the sweep of the Detroit Tigers for San Francisco’s second World Series title in three years.

Later that week, I ventured to Market Street to catch a glimpse of the championship Giants. I’d never seen an area so dense with people since Halloween in Isla Vista. The streets were painted with orange and black confetti.

I’m not a San Francisco sports fan. I was born in Fair Lawn, N.J. When I watch baseball, I watch the New York Mets. The Mets logo was created from Dodger blue and Giants orange. Aside from this shared history, I never cared much for the Giants.

Brett Favre was in the midst of his third consecutive MVP run when I started getting into football, so I’ve always had an affinity for the Green Bay Packers. It hurt to watch the 49ers dismantle the Packers a week before the Falcons game.

But as I took a minute to look around Valley Tavern that Sunday, I felt something. I don’t know if it was my love of sports or being surrounded by the enthusiasm of the fans. It could have been the collision of both. All I know is that it was contagious. It made me connect to a city in a way I never had before. I kept thinking how coincidental it was that the first semester I moved to San Francisco, the Giants won the World Series. Now I’m getting ready for my second semester, and the 49ers are going to the Super Bowl. What are the chances? History tells us there’s a .06 percent chance, to be exact.

I like these odds. I’ve drunk the Kool-Aid, and it’s delicious.