The 2011 Giant Race in San Francisco will send an expected 10,000 participants running Saturday morning and close city streets, affecting traffic and bus routes.

The racing event, which begins at 8 a.m., features a half-marathon and 10K and 5K races, which all end on the field of AT&T Park — home of the World Champion San Francisco Giants.

The race will close streets in The Embarcadero, along Fisherman’s Wharf, Fort Mason and the Presidio throughout the morning, San Francisco Municipal Transportation Agency spokesman Paul Rose said.

The race route will affect San Francisco Municipal Railway service including the F-Market and T-Third lines and the 28, 39 and 49 bus lines, Rose said.

The annual race has raised more than $50,000 for Project Open Hand, an organization that provides meals to seniors and people living with serious illnesses, organizers said.

All participants will receive a medal, shirt, and a bobblehead doll of Giants pitcher Tim Lincecum.  

After the races, participants can attend the Safeway Post Race Expo at AT&T Park. The event will feature food, music, and ballpark vendors.

All road closures are expected to reopen by 1 p.m., Rose said.