CINCINNATI (AP) — Buster Posey hit the third grand slam in Giants' postseason history, and San Francisco completed its startling comeback by holding off the Cincinnati Reds 6-4 Thursday in the decisive Game 5 of the NL division series.

The Giants won the final three games, all in Cincinnati, and advanced to the NL championship series. They will face either St. Louis or Washington.

Ahead 6-0, San Francisco saw the Reds rally throughout the late innings. Cincinnati scored once in the ninth before Sergio Romo struck out Scott Rolen with two runners on base to end it.