At Nationals Park, “Beer here!” can be heard at least as often as chants of “HAR-per!” Cold brews and baseball are a time-honored tradition. Yet Major League Baseball is hoping that wine can field a piece of the action, too.

Why not? Teams have sold naming rights to pitching changes, after all. For the second year, MLB has teamed up with Wine By Design, a New York lifestyle marketing firm with offices in Napa Valley, to produce a line of wines customized for major-league teams.

The MLB Club Series collection features 18 teams, including the Washington Nationals and the Baltimore Orioles. The Chicago Cubs merit two wines in honor of Wrigley Field’s centenary (left over from last year). San Francisco’s Giants, winner of October’s World Series, have four, including three sparkling.

Such custom-branded wine is nothing new. For the MLB Club Series, Wine by Design tapped into a large but mostly unpublicized segment of the wine industry in California that produces labels for retailers such as Trader Joe’s, Total Wine & More, Whole Foods Market and BevMo, as well as corporations, universities and sports leagues.

California produces about 90 percent of all U.S. wine. While the media focuses on artisan winemakers and small-production cuvées, there’s a significant commodity market in bulk wine — excess production or juice that wineries reject for their estate-labeled bottlings. Wine By Design has recognized that some teams are based in wine country. Those San Francisco Giants sparkling wines are produced by Mumm Napa Valley, the California offshoot of the Mumm champagne house in France. The Giants also offer a red blend from Wattle Creek Winery in Mendocino County’s Alexander Valley.

The New York Yankees feature a Finger Lakes Riesling from Anthony Road winery, a top producer, among their four wines. Chaddsford Winery in Pennsylvania contributes one of three wines for the Philadelphia Phillies, and the Seattle Mariners are represented by two wines from Washington state’s Columbia Valley.

But most of the MLB wines are produced by Plata Wine Partners, a Napa company with “access to over 25,000 acres of premium coastal California wine grapes,” according to the company’s Web site. That means they purchase grapes and wine from all over the state. Plata provides wines to retailers, restaurants and wineries.

Plata’s contributions to the MLB wines include Central Coast cabernet sauvignons for the Nationals and Orioles. They are available online from Bounty Hunter, a well-known Napa retailer, for $60 for a three-pack; descriptions for the Nationals and O’s wines contain identical information about varietal blend, alcohol content and vineyard sourcing — which makes me think the wines are the same. (I have not yet sampled them.)

Orioles fans wanting to raise a glass to the orange and black might be out of luck. Maryland law does not permit retailers to ship wine directly to state residents. And baseball’s wine Web site ( www.mlb.com/wine ) does not list local retailers carrying either the Orioles or Nationals label. (The wines are new and are just getting into distribution, according to a Wine By Design spokesman.) The bottles cost about $20.

How are these wines marketed? On MLB.com, the blurb for that Yankees Riesling evokes Brooklyn stickball and the Bronx Bombers as proof that “New York is sacred baseball country,” then adds that in recent years “it has also become great wine country.” Baltimore’s notes that from Camden Yards, one can see “both branches of the Patapsco River, Interstate 95 and the B&O Railroad.”

And how does Major League Baseball market the Washington Nationals cabernet sauvignon? With the power of Bryce Harper’s swing or the finesse of a Gio Gonzalez curveball?

Nope. We get traffic.

“Sometimes you feel like you’re locked up on the Beltway at 6:45,” the MLB sales pitch says. “What would it take to get you where you want to be? Surprisingly little: A ballgame and a glass of good wine.” Really? We’re drinking while stuck in traffic? “Powerful flavors of blackberry get it done with zero gridlock.”

A political reference, of course.

“These days people take the Nationals and their Cabernet just as seriously as what comes down from the Hill.”

Even if the wines can be found at the park, I’ll stick with beer when I’m there. And make it local. You’ll find me just before first pitch at the bar in the Red Porch, ordering a Flying Dog Blood Orange Ale.

A previous version of this story misstated the location of Wattle Creek Winery. It is in California’s Alexander Valley.

McIntyre blogs at dmwineline.com. On Twitter: @dmwine.

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