SAN FRANCISCO, Aug. 7 — Barry Bonds swung and then immediately threw his arms in the air, realizing that he had become the most prolific home run hitter in major league history. Everyone in the ball park instantly realized the importance of what they had witnessed as well, watching Bonds’s latest and most important white streak soar into the night.

Bonds’s 756th homer pushed him past Hank Aaron and pushed baseball’s history into an awkward spot. He is alone now atop the career home run list. Let the debate about the authenticity of Bonds’s record begin. It will be here for a while.

With his devastating, compact swing, Bonds blasted a fastball from Mike Bacsik of the Washington Nationals over the fence in right center field in the fifth inning. The eager San Francisco Giants fans, who were already standing and hoping to watch their hero create history at AT & T Park, cheered, hugged and high-fived. Some even wept.

When Bonds reached home, Nikolai, his 17-year old son and a Giants’ bat boy, was there to greet him. Nikolai held up one finger to his father, a sign that Bonds was No. 1. Bonds stopped at the plate, and raised his arms high again, then pointed to the sky, a tribute to his late father, Bobby.