With seven sophomores and a dozen freshmen on his depth chart, Hurricanes defensive coordinator Mark D’Onofrio has endured a season’s worth of growing pains through seven games.

This University of Miami defense — the youngest in the Atlantic Coast Conference with as many as seven first- or second-year players who are slated to start Saturday night against 12th-ranked Florida State — is on pace to give up more points, more yards (rushing, receiving and total), more first downs and produce fewer sacks than any Hurricanes team ever.

But while Hurricanes fans grit their teeth in anger and frustration each time an opponent blows past one of D’Onofrio’s young players, the 43-year-old former Penn State linebacker remains headstrong. He said his defense will grow up and eventually turn the corner. D’Onofrio said he saw glimpses of growth — particularly from his young corners and defensive tackle — in the second half of Saturday’s 18-14 loss to North Carolina, when UM gave up just three points and 173 yards.

But this week’s showdown with the Seminoles — ranked sixth in scoring (46.0 points per game), 12th in total offense (530.57 yards per game) and armed with 6-5, 240-pound quarterback EJ Manuel (fourth-highest rated passer in the FBS) — might turn out to be a challenge that is just out of the Hurricanes’ league.

“The stats speak for themselves,” D’Onofrio said. “The visual and picture of watching the tape does it even more justice for me. Manuel is just tremendous, and he has a tremendous supporting cast.

“It’s not a matter of saying you’re going to take one guy away. You have to play team defense, and you have to execute. We were better last week, but we have to execute a lot better if we’re going to win.”

The Hurricanes, who rank 118th out of 120 FBS schools in rushing defense (253.71 yards per game), 117th in total defense (506.57) and 93rd in scoring defense (32.29 points per game), already have made some moves this week to prepare for FSU’s speed, size and athleticism.

Sophomore Denzel Perryman, who started all five games he has played in at middle linebacker, was moved to the weak side (where he played all of last year). Junior Jimmy Gaines, sophomore Gionni Paul and freshman Raphael Kirby will all split time in the middle, D’Onofrio said, “with whoever practices the best getting the start,” and “whoever plays the best” getting to finish Saturday’s game.

“Denzel and Eddie [Johnson] are probably our two fastest guys,” D’Onofrio said. “This gives us the ability to have guys who can cover in space, who can handle screens when they’re thrown to the perimeter and who can blitz off the edge, do those type of things. I think it suits us better where the guys competing for the mike position are better suited to find the ball inside and maybe not play in space as much.”

A year ago in FSU’s 23-19 win in Tallahassee, the Hurricanes produced three sacks for 17 yards and kept themselves in the game by limiting the Seminoles to just 63 yards rushing. This year, FSU’s offensive line is much improved. It is giving up just one sack every 43 snaps (it was one sack every 20 snaps in 2011). UM’s defense, meanwhile, hasn’t produced a sack in its past two games and is on pace to finish with just 12 on the season — four fewer than its previous worst (16) in 1984.