SANTA CLARA, Calif. — With injuries mounting, the San Francisco 49ers have made a significant adjustment to their preseason schedule, announcing Sunday that they’ve canceled their planned joint practices with the New Orleans Saints.

“The 49ers and Saints have mutually agreed to cancel the joint practices that were scheduled in Irvine on Thursday, Aug. 15 and Friday, Aug. 16,” the Niners said in a statement.

Those joint sessions had been slated to take place in Irvine, California, where the Saints have been training, before the teams were set to play a preseason game next Sunday at the Niners’ Levi’s Stadium in Santa Clara.

A source told ESPN that the driving force behind the decision was the numerous injuries that have plagued the 49ers during camp. A variety of soft tissue ailments have prevented multiple players from participating in practice for more than a week.

When the Niners practiced Thursday, a whopping 23 players did not take part for various reasons. And injury hit again in the their preseason opener against the Tennessee Titans on Saturday night, with cornerback Ambry Thomas suffering a broken right hand that is expected to keep him out for an extended period.

Running back Christian McCaffrey (calf), linebacker Fred Warner (foot), guard Spencer Burford (hand) and wide receiver Ricky Pearsall (shoulder) are among the key Niners who have been out of practice of late. That doesn’t account for the absences of left tackle Trent Williams and wideout Brandon Aiyuk, who are holding out and holding in, respectively, amid contract-related disputes.

Canceling the practices is a disappointing development for Niners coach Kyle Shanahan, who traditionally has viewed those sessions as a better gauge of his team than preseason games.

“It’s awesome to get a chance to scrimmage against people,” Shanahan told reporters Saturday in Nashville. “We’re a little banged up. So, we’ve got to figure out how we can pull that off and stuff like that.”

The answer, it turns out, is that they can’t. The Niners would have had to stretch to have the needed bodies for those practices to be as productive as hoped. Instead of traveling to Irvine, the Niners plan to practice at home in Santa Clara on Monday, Wednesday, Thursday and Friday this week before Sunday’s exhibition game against New Orleans.

Saints coach Dennis Allen said it was disappointing to have to cancel the joint sessions but that he was not concerned about it. He said his team would look at possibly scheduling practices against another squad but that he didn’t anticipate it coming to fruition.

“I think we’ll probably take some of that planned work we had against the 49ers and the skeleton of that and just utilize that to work against ourselves,” Allen said.

ESPN’s Katherine Terrell contributed to this report.