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The Seals gave way to the Giants in 1958, and in the years since both Anchor Brewing and the Giants have become San Francisco icons.
For Greggor, a partnership with the city's baseball team is essential.
"Our history goes back a long, long time, so we would feel uncomfortable not being part of the Giants institution," he said. "Having that long-term connection is something we see as being terrific for us and the city of San Francisco."
The partnership has expanded in recent years. Last season the Giants unveiled the Anchor Plaza and Taproom inside AT&T Park. The area is located on the outfield concourse of the stadium and includes a re-creation of Anchor's original tap room.
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Anchor Plaza has become a meeting place before and during games, helping to draw people back to the concession stands located in the area.
"Anchor Plaza has become a destination for our fans," said Mario Alioto, senior vice president of business operations for the Giants. "It's a popular gathering point in the ballpark, and the Anchor brand adds a local connection that our fans identify with."
AT&T Park has become the top spot for Anchor Brewing sales, with the brewery selling more beer at the field than anywhere else in country. According to Greggor, Anchor Brewing sales increased 50 percent at AT&T Park last year.
The association between Anchor Brewing and the San Francisco Giants will grow deeper in the coming years, with Anchor building a second brewing facility across the street from AT&T Park. The project will include a restaurant and museum and is part of a $1.6 billion urban development project being led the Giants.
For Greggor, the marriage of the two San Francisco icons extends well beyond the ball park.
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"Our connection is much more an emotional city connection, and Anchor Brewing's connection with the Giants is appreciated by their fans and raises our profile all around Bay Area bars and restaurants," he said. "It's a connection that makes people feel good about San Francisco, makes them feel good about the Giants and about Anchor Brewing."