The final postseason position in the American League could be determined on this final Friday of the regular season.

Both Kansas City and Oakland are in position to clinch wild card spots. The Royals can either do it with a win over the White Sox tonight, or a loss by Seattle at home against the Angels. Los Angeles has 18-game winner Jered Weaver scheduled to take the mound. Seattle goes with slumping 14-game winner Hisashi Iwakuma (hee-sash-ee ee-wah-koo-mah), who has lost his past three starts, allowing 15 earned runs in 12 innings.

Oakland also needs the Mariners to lose and must win against Texas to make it into the postseason.

Kansas City is still chasing Detroit for the AL Central title. The Tigers can put an end to that with a win at home against Minnesota, and a KC loss to the White Sox. Detroit is sending 15-game winner Rick Porcello to the mound.

In the National League, St. Louis holds a one-game lead over Pittsburgh for the NL Central title. Pittsburgh tries to keep the pressure on playing at Cincinnati, while the Cardinals hit the road to open a series at Arizona.

The hunt for the best record in each league continues. The Angels can clinch it in the American League, either with a win over Seattle or a Baltimore loss at Toronto.

If Washington sweeps its home doubleheader against Miami, that will close out the Dodgers for home field advantage throughout the playoffs in the National League.

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