After eight seasons, seven Pro Bowl appearances, and five first-team All-Pro honors, San Francisco 49ers linebacker Patrick Willis is reportedly set to announce his retirement from the NFL at the rather young age of 30.

Yahoo Sports broke the news Monday, though no reason for Willis’ premature retirement was given in the report. Presumably, injuries and perhaps believing time could be better spent away from the field are the likely factors behind Willis’ departure from the league.

Willis appeared in only six games last season before a left toe injury and subsequent surgery forced him to sit out the rest of the year. He also missed two games in 2014, which by itself isn’t a lot, but it was a big dip for a player who had missed only four total games in his first six seasons.

Willis is now opting to end his career earlier than expected, and at a significant financial loss. He still has two years and more than $20 million remaining on his current contract, and Willis' departure could certainly leave a huge hole in the 49ers defensive front seven next season.

Fans gushed over Willis’ tremendous career and guffawed at his unexpected retirement on Twitter, where he was also one of the highest trending topics on the social media site for most of the day.

Willis is voluntarily calling it quits, but despite the smaller breadth of his career, there’s little doubt that he belongs in the conversation as one of the greatest linebackers in NFL history.

The conversation of course starts with the likes of former Baltimore Ravens great Ray Lewis, and Hall of Famers like the Chicago Bears’ Mike Singletary and the New York Giants' Lawrence Taylor.

The second and last defensive player to ever win NFL MVP honors, Taylor is considered the gold standard by which all other linebackers are compared. A gifted pass rusher who set a then league-record of 20.5 sacks in 1986, Taylor was a force who changed the outside linebacker position forever.

He claimed two Super Bowl titles with the Giants, in 1987 and 1991, and was named to 10 Pro Bowls and 10 All-Pro first teams in consecutive seasons.

Seven times named a first-team All-Pro, 13 Pro Bowl appearances, and twice tabbed as the Defensive Player of the Year, Lewis was the vocal and on-the-field leader of arguably the greatest defense in NFL history, the 2000 Super Bowl-winning Ravens.

Giving up a miniscule and record-setting 165 total points throughout the regular season, the Ravens steamrolled the league for a 12-4 record and in the postseason won four straight by an average margin of 18 points.

Over the course of 17 years, Lewis would rip off 41.5 sacks and 31 interceptions and most every year the Ravens were favored to make the postseason because of his leadership and tenacity on the field.

Singletary, who was inducted into the Hall of Fame in 1998, spent five fewer years in the league than Lewis but his impact was just as great. He was the headliner for the 1985 Chicago Bears, a group often compared to Lewis’ Ravens for how they dominated the NFL.

Chicago would finish the regular season at 15-1, and let up 198 total points, with Singletary using his ferocious tackling and competitive nature to intimidate opponents throughout. And during their postseason run, the Bears would give up one touchdown over three games.

Taylor, Lewis and Singletary clearly have a unfathomable Super Bowl run on their resumes, something Willis is conspicuously lacking.

Willis did help the 49ers reach three straight NFC Championship games under former head coach Jim Harbaugh, and nearly toppled the Ravens in 2012 before falling 34-31 in one of the wilder Super Bowls of recent memory.

But in the regular season, in what can now be called Willis’ prime, the 49ers were one of the most feared and consistent defenses in the league. From 2011 to 2013, San Francisco was ranked No. 1 in pass defense, second or third against the run, and no lower than No. 2 in total takeaways forced.

While he doesn’t have the postseason success of Taylor, Lewis or Singletary, Willis’ stats from his best seasons as a pro do stack up. Back in 2009, Willis racked up 4.0 sacks, three interceptions and 114 total tackles, and the next year he’d put up a career-best 6.0 sacks to go along with 101 tackles.

Though he typically served more as a run stopper or a quarterback spy, Lewis’ highest sack total in a single season was 5.0 in 2006. And Singletary never totaled more than 3.5 sacks in any single season. Willis, Singletary and Lewis never came close to Taylor's pass rushing numbers, but again each played the position differently and how they were positioned by coaches goes a long way as well.

The debate isn't confined to just those players. Junior Seau, Zach Thomas, and Brian Urlacher also enjoyed stellar careers. 

If Willis came back healthy next season, he likely could have put up numbers similar to his career average of 91.5 total tackles, 2.6 sacks, and one interception, but maybe the numbers weren’t worth the risk of further injury.

Nevertheless, even in such small window of a pro career, Willis has earned a place among some of the NFL’s all-time great linebackers.