SEATTLE — The most pressing item on the Yankees’ calendar last October was an organizational deep dive.

This year, they can officially clear their schedules for playoff baseball.

There are bigger and better goals on their agenda, but the Yankees took care of the first order of business on Wednesday night by clinching a postseason berth with a 2-1, 10-inning win over the Mariners at T-Mobile Park.

The champagne celebration was temporarily delayed after Clay Holmes gave up a game-tying home run to Justin Turner in the eighth inning.

But Anthony Rizzo, who had two of the Yankees’ three hits and drove in both of their runs on the night, led off the 10th by ripping a double to right field to score automatic runner Jasson Dominguez from second base.

Ian Hamilton then closed it out in the bottom of the inning with some help from a bizarre double play.

Cal Raleigh had led off with a single to put runners on the corners before Hamilton got Randy Arozarena to strike out.

But as he did, Arozarena’s bat went flying down the third-base line, with Julio Rodriguez dancing out of the way to avoid it.

That allowed Austin Wells a chance to throw down to third, where he picked off Rodriguez for the second out.

Hamilton then struck out Turner to end it.