The Yankees’ nightmare weekend in Boston continued to get worse.

First baseman Anthony Rizzo — who left Sunday night’s loss after crashing into Red Sox reliever Brennan Bernardino in the top of the seventh inning — is out 4-to-6 weeks after suffering a fracture in his arm, The Post’s Jon Heyman confirmed Monday.

After hitting the deck, Rizzo rolled over several times and was seen clutching his right wrist area.

The first baseman was immediately removed from the game.

The Yankees are likely to move D.J. LeMahieu to first base and slot utilityman Oswaldo Cabrera at third, according to Heyman.