EVANSTON, Ill.—The Blue Devils' victory against Northwestern Saturday was not as rosy as it may have seemed.

Quarterback Daniel Jones fractured his left clavicle at the end of the third quarter and will be out indefinitely after surgery Sunday morning, per a team release. All-ACC cornerback Mark Gilbert was helped off the field in the first half and is now out for the season after hip surgery Sunday as well.

The two join a growing list of key Blue Devils in the training room, as wide receiver Aaron Young and safety Jeremy McDuffie didn't suit up for Saturday's contest due to lingering injuries.

Losing Jones is a major blow for the Blue Devils. The third-year starter has begun the 2018 season looking stronger than ever, completing more than 74 percent of his 39 pass attempts and posting five total touchdowns without a turnover in Duke's first two contests.

Former Blue Devil quarterback Anthony Boone missed four weeks with the same injury as Jones in 2013. That Duke team went 1-2 in its stretch without Boone, losing a pair of ACC contests.

Jones' injury was the second scare of the game after Gilbert had already left in the first half.

"We have a lot of information on him, we took him to the hospital here," Cutcliffe said after Saturday's game. "Right now, we are figuring Mark [Gilbert] is going to be out for quite some time."

Gilbert's absence would immediately impact a young Blue Devil secondary. He hauled in six interceptions during the 2018 season—which led the ACC— and has become an anchor for a strong defensive unit.

"Mark Gilbert is one of the best corners in the ACC, if not the country," senior linebacker Ben Humphreys said. "We feel for him and I hope he gets healthy fast, and losing a guy like that is never easy."

Quentin Harris and Michael Carter II took over for Jones and Gilbert, respectively. Harris was 2-for-2 on passes for 14 yards with 14 yards on the ground, but did not produce any points. Carter—on the other hand—had the best games of his career, logging eight tackles, three pass breakups and an interception in the victory. 

The Blue Devils will head to Waco, Texas, next Saturday where they will face Baylor at 3:30 p.m. 

This story was updated at 4 p.m. Sunday to include additional information on both injuries.