BOSTON — The Yankees’ franchise has been around since 1903, totaling 18,160 regular-season games. And until now, there had never been a week this miserable: 73 runs allowed over the past seven games, the most in any such stretch in franchise history.

There was a familiar formula for the almost daily humiliations, including Saturday’s 9-5 loss to the rival Boston Red Sox: The starting rotation coughed up the bulk of the runs, the bullpen was not able to plug every hole and the offense could rarely come to the rescue.

Throughout his career, C. C. Sabathia has been adept at delivering a solid performance after a loss or in big moments. He was key during the Yankees’ 2009 World Series title and their 2017 playoff run. But even he could not stop the hemorrhaging on Saturday.

Sabathia surrendered too many hard-hit balls, leading to five runs over four and one-third innings. When he departed, the Yankees trailed by 5-3 — still a winnable game for their potent lineup. But reliever Chad Green could not hold down the Red Sox’ powerful offense, and the Yankees, once again, trudged off the field after a third straight loss at Fenway Park.