The San Francisco 49ers had two key players leave practice early Sunday with rookie receiver Brandon Aiyuk and edge rusher Dee Ford each suffering lower-body injuries.

There was no immediate word on the extent of the injuries.

Aiyuk grabbed the back of his left leg after pulling up on a deep pass during team drills and didn’t return. The first-round pick out of Arizona State had been one of the more impressive players early in camp and is being counted on to be a big contributor this season.

San Francisco 49ers defensive end Nick Bosa (97) gets a hand on defensive end Dee Ford (55) during drills at NFL football training camp Friday, Aug. 21, 2020, in Santa Clara, Calif. (Xavier MascareñasThe Sacramento Bee via AP)

San Francisco 49ers defensive end Nick Bosa (97) gets a hand on defensive end Dee Ford (55) during drills at NFL football training camp Friday, Aug. 21, 2020, in Santa Clara, Calif. (Xavier MascareñasThe Sacramento Bee via AP)

The Niners have been hit hard by injuries at receiver already with starter Deebo Samuel sidelined all of training camp with a broken foot that could force him to miss time at the start of the season. Jalen Hurd tore his ACL during camp and will miss the entire year and Richie James Jr. will miss the start of the season after breaking his wrist during offseason training.

Ford got hurt earlier in practice when he came up limping after a one-on-one pass rush drill. Trainers worked on his lower leg for some time and he didn’t return either.

Ford was slowed by injuries last season when he played less than one-quarter of the defensive snaps for the Niners. He did have 6 1/2 sacks during that limited time and is being counted on to be a big part of the team’s defense.

Backup interior lineman Ross Reynolds also got hurt during 11-on-11 drills. He had to be taken off the field on a cart and the entire offensive line group came out on the field to give him best wishes.

“Hopefully it’s not as bad as it looked,” right tackle Mike McGlinchey said. “It’s obviously very, very tough to see when one of our favorite guys like that goes down.”

The Niners held their fourth straight day of padded practices Sunday as the team tries to get back up to speed after a virtual offseason and late start to camp because of the COVID-19 pandemic.

San Francisco has a scheduled day off on Monday before four more scheduled padded practices starting Tuesday in the final portion of an abbreviated training camp.

The 49ers had already lost a couple of other key players to injuries during camp with center Ben Garland expected to miss a couple of weeks with a sprained ankle and slot cornerback K’Waun Williams out a couple of weeks with a calf injury.

Star defensive end Nick Bosa also missed his second straight day of practice without a specified injury and cornerback Richard Sherman got a day off Sunday.

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