Willis (toe) will announce his retirement Tuesday, the 49ers' official website reports.

Willis dealt with a chronic toe issue for the past few years, finally having season-ending surgery in November. His rehab presumably isn't going as hoped for, and it may be the case that Willis' toe will never be the same. It's unfortunate that such a tremendous player will be forced into retirement, but Willis at least made the most of his eight NFL seasons. He earned five First-Team All-Pro selections, including four in a row from 2009 to 2012. While the Hall of Fame process tends to overvalue longevity relative to peak performance, Willis is still a strong candidate to be enshrined in Canton. The 49ers have a number of issues, but they should actually be in pretty good shape at inside linebacker, with both NaVorro Bowman (knee) and Chris Borland (ankle) expected to be healthy for 2015.

Willis is reportedly strongly considering retirement, csnbayarea.com reports.

Per the report, the 49ers, who are are also poised to lose running back Frank Gore to the Eagles, are now also bracing for the possible retirement of both Willis and defensive lineman Justin Smith. The 30-year-old Willis is coming off a 2014 season in which a toe injury that required surgery limited him to just six games and 34 tackles.

Willis (toe) was placed on injured reserve Tuesday.

The move officially spells the end of the season for Willis, who will needs surgery to repair a strained muscle in his left big toe. Willis hurt the toe in Week 6 but indicated Tuesday that it's something that has bothered him for several seasons. He was hoping it would be better in a matter of weeks, but with the injury not progressing as expected, the door is open for rookie Chris Borland to continue serving as the starting left inside linebacker for San Francisco.

Willis will likely need season-ending surgery on his injured toe, Mike Garafolo of FOX Sports 1 reports.

The 49ers figure to confirm the report soon, but it appears Willis will miss the rest of the season with the toe injury he suffered in Week 6. The 49ers will miss Willis' presence on the field, but with Chris Borland tallying 35 tackles the last two weeks and NaVorro Bowman (knee) returning soon, they do have replacements available.

Willis (toe) is inactive for Sunday's game against the Saints.

While officially listed as questionable coming into the game, it was widely believed that Willis would sit out after being unable to practice at all this week. With Willis sidelined, Chris Borland will get the start next to Michael Wilhoite.

Willis (toe) is questionable for Sunday's game against New Orleans.

Although he's listed as questionable, it's generally believed that Willis will sit this one out after missing all of this week's practices. If Willis does sit, Chris Borland is expected to step in next to Michael Wilhoite.

Willis (toe) is trending toward doubtful availability for Sunday's game at New Orleans, after another missed practice Thursday, CSN Bay Area reports. Defensive coordinator Vic Fangio said as much prior to drills, when he relayed, "It's questionable. As the week rolls on, if he doesn't start practicing at some point then it starts moving to doubtful."

Willis's ledger includes back-to-back absences from practice, leading to the belief that a third consecutive DNP is imminent. If he fails to suit up, Chris Borland is ready and willing to cover inside linebacker in Willis' place.

Willis (toe) didn't take part in Wednesday's practice, the 49ers' official site reports.

Willis has sandwiched two DNPs around San Francisco's Week 8 bye, and if he fails to practice in any capacity by week's end, another absence could come to pass. If he sits out Sunday at New Orleans, rookie Chris Borland would earn another start at inside linebacker.

Willis (toe) is listed as inactive Sunday versus the Rams.

Willis was limited in practice all week, but one DNP and the 49ers' bye week weren't enough to result in active status in Week 9. His absence allows rookie Chris Borland to earn another start at inside linebacker.

Willis (toe) is questionable for Sunday's game against St. Louis.

Willis practiced in a limited capacity all week, but he evidently isn't quite ready to call himself 100 percent healthy. He'll therefore head into the weekend questionable, so his IDP owners will want to have a replacement option within reach for the 4:05 eastern time wave of games Sunday.

Willis (toe) was limited during Thursday's practice, the St. Louis Post-Dispatch reports.

Willis was also limited during Wednesday's session, so despite having last week's bye, the All Pro linebacker's toe is still somewhat bothersome. Friday's practice participation should offer more information regarding his status for Sunday's game versus the Rams.

Willis (toe) practiced in a limited fashion Wednesday, the San Jose Mercury News reports.

More on Willis' status in the coming days, but the linebacker is trending in the right direction as Sunday's game against the Rams approaches.

Willis (toe) was limited in practice Monday, Matt Barrows of the Sacramento Bee reports.

Willis did not play against Denver last week but benefits from a bye this week. His status for Week 9's matchup with the Rams is still up in the air at this point, and a decision likely won't be made until later in the week.

Willis (toe) is out for Sunday's game against Denver.

Willis' absence is a painful loss for a San Francisco defense already without Navorro Bowman (knee), but they have backups with decent pedigree in Michael Wilhoite and Chris Borland.

Willis (toe) is still wearing an orthopedic boot on his left foot, Matt Maiocco of CSN Bay Area reports.

No surprise here; Willis remains very unlikely to play Sunday against the Broncos. With San Francisco on a bye in Week 8, his return will likely come in Week 9 at the earliest.

Willis (toe) didn't take part in Wednesday's practice, the Sacramento Bee reports.

Because Willis is expected to be sidelined through the 49ers' Week 8 bye, he should be ruled out for Week 7 in Denver upon the release of Friday's injury report. In the meantime, rookie Chris Borland will cover one of the inside linebacker spots.

Willis (toe) seems unlikely to play Sunday night against the Broncos, csnbayarea.com reports.

On the plus side, Willis' injury, which coach Jim Harbaugh indicated Wednesday is not turf toe, isn't viewed as a long-term concern. With the 49ers on bye in Week 8 though, we may not see the linebacker back in action before the team's Nov. 2 tilt against the Rams. If Willis sits out Sunday's game, Chris Borland would be in line for an expanded role in the 49ers' defense in Week 7.

Willis (toe) is considered unlikely to play Sunday against the Broncos, NFL.com reports.

Willis was seen sporting an orthopedic boot after leaving Monday's game against the Rams in the second quarter with a sprained toe. The 29-year-old is expected to see a specialist in the days ahead, the same one the evaluated Bengals wide receiver A.J. Green, but it sound like he'll be held out at least through the 49ers' Week 8 bye. Look for third-round pick Chris Borland to take on a significant role against Denver, if Willis is indeed forced to miss the game.

Willis suffered a toe injury in Monday's game against the Rams and will not be able to return, Matt Maiocco of CSN Bay Area reports.

With Willis out, rookie Chris Borland will be the next man up to fill the void left in San Francisco's defense. Willis will likely be evaluated in the coming days to determine the severity of his toe injury and availability for the 49ers' upcoming game against the Broncos on Sunday.

Willis led all San Francisco defenders with eight tackles (six solo) in Sunday's win over the Chiefs.

Willis bounced back after a three-tackle performance against the Eagles last week. He gets another favorable matchup against an inexperienced Rams' offense next week.