The San Francisco 49ers were absolutely ravaged by injuries last season, which played a massive role in their disappointing 6-11. And once again this summer, the 49ers are once again experiencing medical issues.

The 49ers announced a handful of roster moves on Wednesday. They have signed offensive lineman Michael Dunn and wide receiver Malik Knowles to their 90-man roster. They released defensive lineman Demone Harris and waived running back Corey Kiner with an injury designation in corresponding moves.

As the deadline to cut down rosters from 90 to 53 approaches, the San Francisco 49ers have some tough decisions to make. Some decisions are inevitable due to the injury bug the team has faced in training camp and the preseason, but unfortunately, some good football players will fall victim to the numbers game of roster cutdowns.

The 49ers wisely have some key veterans, most prominently Nick Bosa, Christian McCaffrey and Trent Williams, on schedules designed to keep them fresh and out of the fray from time to time. Quarterback Brock Purdy is a leader in a more reserved, analytical way. Deommodore Lenoir is stepping up to push the secondary.

The 49ers have committed to Brock Purdy with a big extension. But the key to that deal is the guy standing behind him in the backfield.

San Francisco 49ers cornerback Chase Lucas has consistently made plays in training camp and preseason. He explained why after the win over Las Vegas.

"If the 49ers want to lighten Christian McCaffrey's workload, they must add a durable running back to the rotation," Moton wrote. "Robinson can grind out yards between the tackles, which would allow McCaffrey to stay fresh for the length of the regular season."

Here's who stood out on Day 16 of 49ers training camp. Keep in mind, Mac Jones sprained his knee in the 49ers' preseason win over the Raiders on Saturday.

The San Francisco 49ers have needed an offensive lineman to step up at guard and an undrafted rookie is doing just that through two preseason games.