The A's clinched a wild-card spot before they hit the diamond Friday night in Seattle.
Cleveland's loss will send Oakland to the playoffs.
Cleveland lost 8-2 in the 7th against Washington.
It is the second straight season the Athletics have made it to the MLB playoffs.
The A's can also punch their ticket to the postseason with a win over the Mariners.
Oakland A's clinch wild-card spot, headed to playoffs