Jeffery's best reception may have been one out of bounds in the third quarter after he tipped up a long pass between two defenders and lunged for the catch that didn't count.
Garcia was 14 of 30 for 227 yards.
Clemson, meanwhile, suffered through the offensive problems that have plagued it the past month.
The Tigers managed 39 yards of offense after Hopkins' touchdown less than two minutes into the game.
Swinney even brought in injured Andre Ellington, the team's leading rusher who's been out since Oct. 30 with foot problems, for a spell. But he didn't gain any ground, either.
It was a bad end for quarterback Kyle Parker, Clemson's two-sport star who gave up $800,000 in additional money from the Colorado Rockies to play one last season for the Tigers.
Just a sophomore, he had a solo run down Death Valley's hill on Senior Night because he previously announced he wouldn't return.
But Parker got an earlier exit than expected after Antonio Allen returned an interception 36 yards for a touchdown in the third quarter. Backup Tajh Boyd took over for Parker, who threw 20 touchdowns a year ago.
Parker was 7 of 17 for 117 yards. He didn't stick around to answer questions, leaving some to wonder if he'd stick around the team at all with just a lower-tier bowl game ahead.
"I always want the best for Kyle," Boyd said. "I wish he could have finished his last game here, but I think everything happens for a reason."
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