Linebacker Clay Matthews is one of 25 modern-era semifinalists for the Pro Football Hall-of-Fame’s Class of 2021, and nothing new there. He’s been a semifinalist five times, including the past three years. But he’s never been a finalist for Canton, and that must change.

Now. Or else.

Because if he fails to reach the Final 15, Clay Matthews may never have another chance to have his case heard by the Hall’s board of 48 selectors. Reason: He’s in his 20th – and final – year of eligibility as a modern-era candidate, which means a failure to become a finalist would condemn his candidacy to the senior pool … and good luck.

That category is defined as players retired more than 25 years and whose 20-year candidacies have expired. But let’s be honest: It’s more than that. It can be purgatory. Canton’s version of a vortex, the senior class pulls qualified candidates down into a morass of all-decade stars and All-Pro luminaries so thick that some – no, most – seldom have their candidacies revisited.

I’m serious.

Consider that our Rick Gosselin counts 59 all-decade members – players considered elite at their positions – in the senior pool. Among them is former Eagles’ lineman Al Wistert, who in nine seasons with Philadelphia was an eight-time All-Pro, two-time NFL champion, all-decade choice and MVP on the only NFL club to post back-to-back shutouts in league championship games (1948-49).

Imagine that resume with one of today’s candidates. He’d be a first-ballot cinch. Yet Wistert, passed over for this year’s Centennial Class, remains buried among the dozens of Hall-of-Fame-worthy choices that Clay Matthews seems destined to join. Which is why I want the board to hear his case now.

Because it may never again.

Look, I understand the odds of his reaching Canton in his last year of eligibility. They border on the Jets’ chances of reaching Super Bowl LV. But at least the Jets gain another chance next year. And the year after that … and the year after that.

Clay Matthews may not.

The senior pool, which once had two Hall-of-Fame finalists each year, was reduced to one candidate every other year when in 2014 the Hall’s board of directors created the contributor category. Then, when the board this year devised the coaches’ category, it cut the senior finalists again – this time to one annually through at least 2024.

To see what that means for someone like a Clay Matthews, look at the 10 senior finalists left out of the Hall’s. Centennial Class of 2020. Roger Craig didn’t make it. Cliff Branch didn’t make it. Randy Gradishar didn’t make it. Al Wistert didn’t make it.

Barring a Super Bowl III-like upset, Clay Matthews joins them when the Hall announces its Class of 2021 finalists in early January … and not because he’s not worthy but because he’s in his last year of eligibility. Worse, he’s in his last year of eligibility as someone who never was a finalist.

I saw how that went down with defensive back Everson Walls in 2018. Named a finalist in his last year of eligibility, he failed to generate sufficient support to survive the first cut to 10. But that’s not the point. He had his case heard, which is what he and deserving candidates like Clay Matthews deserve.

Matthews played 19 years and was one of the league’s most effective and durable linebackers. He played in 278 games, had 1,561 tackles and was a four-time Pro Bowl choice when that accolade meant something. He also set the Cleveland Browns’ franchise record for career sacks.

Inducted into the Browns' Ring of Honor in 2019, he became the first player in team history to gain that honor without first being enshrined in Canton.

“Clay’s longevity is indisputable,” said Hall-of-Fame voter Tony Grossi, who covered Matthews during his tenure with the Browns, “but it is not his only qualification. He played every linebacker position in a 3-4 system from year to year and remained the best player on his various defenses – no matter which role he selflessly filled under five head coaches.”

In 16 seasons with Cleveland and three with Atlanta, Matthews' career included (according to statistics compiled by Pro Football Journal) 16 interceptions, 28 forced fumbles, 14 recoveries, 82-1/2 sacks and five seasons with 100 or more tackles. According to Gosselin, he also had four blocked field goals.

“He was a four-down linebacker,” Gosselin wrote in 2015 (State Your Case: Clay Matthews (si.com), “who played the run, rushed the passer and covered both receivers and kicks. At the age of 39, he made three special-teams tackles.”

And at the age of 40, he set a record as the oldest player (40 years, 282 days) to produce a sack. That was his last NFL season, and he went out with a flourish. As a right defensive end, he led the Falcons in sacks that year with 6-1/2.

The knock on Matthews is that he was named to no more than four Pro Bowls, was never a first-team All-Pro, wasn't an all-decade choice and didn’t reach a Super Bowl. OK, I get it. But he did enough in his career to convince Hall voters to bring him back again and again as a semifinalist.

There must be a reason.

Does he belong in the Hall? I don’t know. But I'd like to find out. This is his last chance to have his case heard as a modern-era candidate. So let’s hear it. Clay Matthews deserves nothing less.