Clemson quarterback Cade Klubnik twisted his ankle in the third quarter of the Tigers' 41-10 win against the Boston College Eagles in Week 7. He limped to the medical tent and was replaced by backup quarterback Christopher Vizzina for the rest of the routine win. According to a report by On3 reporter Larry Williams on Thursday, the polarizing Klubnik has been limited in practice all week and will be a game-time decision in the Tigers' Week 8 clash against the SMU Mustangs. "There is significant concern within the football program about Cade Klubnik’s ability to play Saturday against SMU, @LarryWilliamsTI reports. Klubnik suffered a sprained ankle late in the third quarter of Clemson’s win at Boston College," the On3 report stated.Earlier in the week, embattled Clemson coach Dabo Swinney gave a positive update on Cade Klubnik's availability for the Tigers' Week 8 clash against the Mustangs. “He’s sore but expect him to play (vs. SMU),” Swinney said. “We’ll be smart with him, and we got almost a week before game time. The main thing is just getting him to make sure he’s got the plan down. We've just been taking our time with him. He's gone from day to day to hour to hour... literally, getting better every hour."Cade Klubnik replacement backed to performAfter Cade Klubnik limped off in the third quarter of Clemson's win against Boston College, Christopher Vizzina led the Tigers for the rest of the game. This season, the sophomore redshirt has played in three games and has thrown for 37 yards on 50% completion, while rushing for 21 yards on seven carries.During his weekly news conference, Clemson coach Dabo Swinney backed Vizzina to replace Klubnik, should the QB1 not be fit enough for the clash against the SMU Mustangs. "Yeah, I mean, those guys took a ton of work, and done a great job," Swinney said. "If Cade can't go, CV's the guy, for sure. Got confidence he could go get it done. "We gave him a ton of work this spring and a bunch of work in fall camp with the ones, and he really did a nice job. He performed very well in all those opportunities."Vizzina will have big shoes to fill should he get the nod against the Mustangs on Saturday. Despite shaky performances this season, Cade Klubnik has 1,530 passing yards, 11 touchdowns and 5 interceptions, while adding 104 rushing yards and 2 touchdowns.