Clemson and Florida State largely have run the Atlantic Coast Conference of late, winning 13 of the last 14 conference championships between them.When they meet Saturday in South Carolina, they’ll be fighting for something far less significant: bowl eligibility.The Tigers (3-5, 2-4 ACC) and visiting Seminoles (4-4, 1-4) have struggled to find consistency this season, although Clemson’s struggles are far more surprising.The Tigers began the season fourth in the AP Top 25 poll.After last week’s 46-45 home loss to Duke, the Tigers’ streak of 20 straight bowl appearances is in serious jeopardy.”Hard to put into words the disappointment,” Clemson coach Dabo Swinney said. “Very frustrating.”The biggest disappointment is the defense under new coordinator Tom Allen. After the Tigers finished each of the previous nine seasons in the top four of the ACC in scoring defense, this year’s Clemson defense ranks 10th, allowing 24.0 points per game.Clemson outgained Duke by 121 yards but allowed the Blue Devils to amass 158 yards and 11 points in the fourth quarter.”Defensively, just not much good,” Swinney said. “… I feel like it’s back-to-back games we’ve lost to Clemson with a bunch of big-play busts and poor awareness.”