SAN FRANCISCO -- The Giants began their 10-game homestand with a 2-1 win against the Rockies, taking one step closer to clinching the National League West.

The club extended their division lead to a season-high eight games over the idle Dodgers, and their magic number shrank to eight games, meaning that any combination of Giants wins or Dodgers losses totaling eight would give San Francisco its second division title in three years.

"You'd like to hopefully keep that margin of error and go hard every day," manager Bruce Bochy said. "Every one of these games are important. We're not taking anything for granted. We have our work cut out for us against some pretty good teams, and that's how you have to approach it."

Tuesday's key games to watch (all times PT)

Dodgers (Harang, 9-9) at Nationals (Zimmermann, 10-8), 4:05 p.m. Preview >

If the postseason started today ...

This is how the teams would match up: Postseason Bracket »

Postseason 101

Magic numbers
To calculate a team's magic number, take the number of games it has remaining and add one. Then subtract the difference in the number of losses between that team and its closest pursuer.

Tiebreaker scenarios
A tiebreaker game will be played to determine a division winner, even if the tied clubs are assured of participating in the postseason. If a division championship tiebreaker is necessary, the head-to-head record between the clubs will determine home-field advantage. If the head-to-head record is tied, then the division record will be the next tiebreaker.

If two clubs are tied for the two Wild Card berths, home-field advantage will be determined by the head-to-head record between the clubs. If the head-to-head record is tied, then the division record will be the next tiebreaker.

Tiebreaker rules »

2012 postseason schedule
Wild Card playoff games: Oct. 5
Division Series: Oct. 6-12
AL Championship Series: Oct. 13-21
NL Championship Series: Oct. 14-22
World Series: Oct. 24-Nov. 1