Dan Campbell doesn’t mince words. So when the Dolphins’ tight ends coach sat down an underperforming Charles Clay awhile ago, his message was characteristically blunt.

“[I] hit him right between the eyes with it,” Campbell recalled. “I don’t sugarcoat anything. I tell it like it is.

“[But] he takes that, looks you right in the eyes, and he agrees. He knows, ‘You’re right. I’ve got to be better.’ ”

Eleven games into the season, Clay finally followed through.

The second-year H-back had the breakout game the Dolphins have long needed Sunday, setting career highs with six catches for 84 yards. His performance included a game-tying, 29-yard touchdown catch on a wheel route, getting behind the Seahawks defense by a good 5 yards.

But Clay did more than simply catch the ball. He was on the field for 37 of the team’s 60 snaps — his highest participation percentage of the season — and made a devastating block on Seattle’s Chris Clemons to help spring Reggie Bush on his touchdown run.

“That’s what I am trying to do — be an all-around player,” Clay said.

The coaching staff wants the same. Campbell said this week that Clay, at his best, reminds him of Keith Byars — the versatile fullback/tight end who spent parts of four seasons in Miami.

Byars could line up in the backfield or put his hand in the dirt next to an offensive tackle. He finished his career with more than 3,000 yards rushing and nearly 6,000 yards receiving on 610 catches.

Byars could bust the seam on a defense, much like the Patriots’ tight end duo of Rob Gronkowski and Aaron Hernandez. The Dolphins catch a bit of a break when New England comes to town this weekend. Gronkowski is out with an arm injury; when healthy, he is probably the biggest threat on the league’s best offense.

“I think the ability to attack the middle of the field in this modern era of the National Football League … is a critical element,” Dolphins coach Joe Philbin said. “I think we’re starting to do a little better job ourselves.”

That’s thanks to Clay, who has eight catches and two touchdowns over the past four weeks after managing just five receptions — and no scores — in the season’s first seven games.

Campbell believes Clay can be a difference-maker, not just because of his versatility, but also because of the way defenses have played the Dolphins this season — with a great deal of success recently, at least until the second half of Sunday’s Seahawks game.

Opposing teams have regularly dropped a safety into the box to take away the run, and jammed receivers Brian Hartline and Davone Bess at the line to disrupt the intermediate passing game. They have mostly gotten away with it because the Dolphins have had no one to challenge gambling linebackers and safeties down the middle of the field.

Anthony Fasano has been a dependable safety valve for Ryan Tannehill, but he’s only averaging 7.8 yards per reception — worst among tight ends with at least 20 receptions.

Clay showed he can get open downfield, creating enough separation to make it easy on his rookie quarterback. Part of the reason Clay dropped to the sixth round of the 2011 draft was his 40-yard time (he ran it in the 4.70-second range), but Campbell said he plays faster than that on Sundays.