The San Francisco 49ers may have some injury reinforcements coming soon.

Players who were on IR or the PUP list for Week 1 are now officially eligible to return from their respective injury lists as the NFL calendar turns to Week 5.

NFL rules stipulate players have to be on IR or PUP during the regular season for at least four weeks. The 49ers’ win over the Denver Broncos was the last game their group of six players who were on IR or PUP for Week 1 were required to sit.

So where do things stand with those 49ers players eligible to return from IR and PUP?

Here’s the rundown:

WR Christian Kirk (calf)

Kirk was one of two players the 49ers placed on IR at final cuts. He’s eligible to return for Week 5, but head coach Kyle Shanahan on Monday said it may be another week before the veteran receiver returns.

“No, I was not told that we’d have him this week,” Shanahan said. “So hopefully next week.”

The 49ers may lean on Kirk quite a bit if he returns while Mike Evans is still banged up and Demarcus Robinson is still on IR. They may also take their time ramping him up since he was injured so early in training camp.

OL Austen Pleasants (knee)

Pleasants is the other player the 49ers placed on IR at final cuts. He’s also eligible to return, although he wasn’t brought up when Shanahan spoke with reporters on Monday’s conference call. Pleasants injured his knee in the 49ers’ second preseason game. When he does return he’ll give San Francisco some additional depth on the offensive line.

LB Nick Martin (hamstring)

The 49ers kept Martin on their 53-man roster before placing him on IR. There’s no word on a timeline for his return as he works back from a hamstring injury he suffered late in the preseason. He’s eligible to return in Week 5, but there may be designs of keeping him on IR all year given the limited number of return designations the team has.

CB Nate Hobbs (groin)

Hobbs is another player who was on the initial 53-man roster before being placed on IR. He missed virtually all of camp dealing with a couple of different injuries, but the 49ers saw enough to keep him around as an insurance policy in their secondary. It looked initially like he’d be an IR stash for San Francisco, but Shanahan on Monday said there’s a chance he’s activated for Week 5 if CB Upton Stout can’t play because of a shoulder injury.

“He can be an option too,” Shanahan said. “Got to see exactly where his rehab’s at. I know he’s getting close, but that would be an option also.”

Hobbs has played in 62 games with 43 starts in his career with the Las Vegas Raiders and Green Bay Packers. He has three interceptions and 21 pass breakups.

DL Mykel Williams (knee)

We’re looping Williams in here because his eligibility to return is the same as the players on IR. Because he’s on the PUP list the team was able to open his practice window early. He was back on the practice field ahead of Week 4 and now the team is hopeful he’ll be able to suit up in Week 5 at Seattle.

“Mykel, hopefully practice keeps going well, has a good week of practice and hopefully we can get him activated at the end of the week,” Shanahan said. “But, it depends how the week goes.”

If he does get activated he won’t count against the team’s eight IR returns.

RB Isaac Guerendo (chest)

Guerendo is also on the PUP list after suffering a pectoral injury during the offseason program. It’s unlikely we’ll see him back any time soon. Shanahan on Friday before the team’s Week 4 matchup with the Denver Broncos said there’s no update on the third-year RB.

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This article originally appeared on Niners Wire: 49ers injury news: 6 players now eligible to return from injured lists

Reporting by Kyle Madson, Niners Wire / Niners Wire

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