A week after committing a season-high 10 penalties in its blowout win over Georgia Tech, Boston College football remarkably displayed even worse mental discipline in its 47-2 road loss to Duke (6-2, 3-2 ACC) on Saturday.

In the first half alone, BC (4-4, 2-3 ACC) nearly racked up as many penalty yards (94 on 11 penalties) as total offense (109), and it finished the game with 15 for 132.

“It was tough, especially in the first half,” said Eagles quarterback Mason McKenzie, who finished the game with a season-low 87 passing yards and 24 rushing. “Felt like we kind of were getting things going finally, moving the ball well, and then it would just be 15 yards or 10 yards, and it's just things that we can't do. We just got to be more disciplined in that area, and that’s all you can really say about it.”

Defensively, the Eagles were flummoxed by Duke running back Nate Sheppard, who entered the contest as a top-five back in the nation in terms of rushing yards and touchdowns.

He would end up accumulating five rushing touchdowns with 129 scrimmage yards on 21 touches, setting the program’s single-game touchdown record on the ground, including tying the single-season record for rushing touchdowns — Sheppard got up to 14 on the year with the monster performance.

“Just a guy like him, we got to make sure we stand our gaps, not peeking on other guys, because he will [make you pay],” safety KP Price said. “Maybe [he tries] to hit one [lane] that’s clogged up, and he’s fast enough, quick enough, to change direction and go into another one.”

The Blue Devils were relentless up front, meanwhile, sacking BC’s quarterbacks — both backup Grayson Wilson and freshman third-string Femi Babalola entered the game in the fourth quarter — a total of six times while collecting 11 tackles for loss, the two of which combined for 78 yards lost for the Eagles.

The only touchdown Duke did not score via Sheppard’s legs came in the second quarter, when quarterback Walker Eget lifted a five-yard touchdown pass to tight end Jeremiah Hasley to cement a 27-2 lead for the Blue Devils, which they took into the half.

BC’s only points were scored on a botched extra-point attempt after Sheppard’s second rushing score of the game in the late stages of the first quarter, as Gavin Strange’s kick was blocked after his holder fumbled the snap.

Defensive back Carter Davis recovered the ball and jogged all the way into the end zone to cut the Eagles’ deficit to 13-2, but that minor glimpse of hope was extremely short-lived.

Strange nailed two field goals in the fourth quarter, one of 41 yards and a 24-yarder, to make it a 47-2 final.

“It was just, it was a bad day,” O’Brien said. “It was a bad day for everybody, and we just have to regroup and start getting ready for Florida State tomorrow."

When asked why his players did not seem prepared for competition, O’Brien did not have a resolute answer.

“I don't know, I didn't do a good enough job,” O’Brien said. “I did not do a good enough job of getting them prepared to play."

The Eagles take on the Seminoles back in Chestnut Hill, Mass., next Saturday at 12:00 p.m. ET.