Yankees fans are angry with Manny Machado.

Why, exactly, is unclear.

They hammered the Padres shortstop with boos in pregame warmups and for his first at-bat in Monday’s game at the Stadium before he struck out against Chad Green. They later booed him in the field, as he caught a pop-up.

Machado was viewed for some time as a potential future Yankee, and he did visit The Bronx over the winter, but they never made him an offer.

The Yankees were not willing to come close to the 10-year, $300 million deal Machado received from the Padres in February.

Perhaps Yankees fans didn’t get the memo.