CLEMSON — Nearly nine months after the defensive debacle at the Orange Bowl, Clemson’s defense demonstrated in a 49-37 loss at Florida State on Saturday that its issues cannot be solved simply with a coordinator change.

Clemson coach Dabo Swinney decided to make a change at defensive coordinator after the Tigers allowed 70 points to West Virginia in the Orange Bowl in January. But on Saturday night, Clemson allowed 667 yards at Florida State, the second worst total in school history.

Defensive coordinator Brent Venables has simplified play-call language. He implemented a new hybrid position designed to better combat spread offenses. He has brought more zone concepts from Oklahoma, but the results have been in many cases worse than a season ago.

No. 17 Clemson (3-1, 0-1 Atlantic Coast Conference) will look to make major strides on defense at 3:30 p.m. Saturday (ESPN2) when Clemson travels to Boston College.

“We certainly didn’t play well defensively,” Swinney said. “We had 15 or 20 plays that were disappointing. We were poor against the run. We gave up big plays. Poor tackling. And we didn’t play with a lot of confidence, particularly at corner.”

After four games, Clemson ranks lower in total defense than it did last season under former coordinator Kevin Steele. Clemson is 95th in the nation in total defense, allowing 443 yards per game, after finishing 83rd in the nation last season, allowing 394 yards per game.

Clemson is 103rd in rushing defense this season (207 yards per game) and like last year struggled with an athletic mobile quarterback in E.J. Manuel on Saturday night as Manuel broke the 100-yard barrier. Clemson allowed 176 rushing yards per game last season, which ranked 71st nationally.

Clemson ranks 111th in the nation — out of 124 qualifying Division I FBS teams — in yards allowed per rush, allowing a full yard more per rush (5.4) than last season (4.4).

While the coordinators have changed, more than half of the starting personnel (six players) have returned. Might the problems be more personnel related? Might the staff need to look at shaking up the depth chart?

“I think anything is possible,” Swinney said. “There are some guys right now we need to challenge. … We have some guys that have to play better. We definitely have to challenge a few guys to perform better. We just don’t have a lot of depth in the secondary. We have some guys coming, but they just aren’t ready.”

Swinney said freshman Travis Blanks, playing the hybrid position, is not a candidate to move to corner.

In talking to reporters after the game, Venables took much of the blame. He also said the entire unit will be evaluated.

“It starts in the run game,” Venables said. “You have to go back and look at personnel and see what we were asking them to do. There are a lot of things — scheme and personnel — we have to evaluate.”