No. 2 Duke has been excelling in most areas, and yet it’s not all good news going into the weekend.The Blue Devils could be down a couple of players, as injuries have struck at an inopportune time.So how Duke reacts to the latest roster fluctuations will be worth charting when Florida State arrives in Durham, N.C., for Saturday night’s Atlantic Coast Conference game.Duke (25-3, 16-1) has a five-game winning streak, with an average margin of 31 points. With eight conference victories by more than 25 points, it’s the most at that level in one season in ACC history.”We know what’s ahead,” coach Jon Scheyer said. “We know the battles we’re going to be in. We know it can happen any night.”Junior guard Tyrese Proctor left with a knee injury during Duke’s 97-60 romp Tuesday night at Miami. He’s out indefinitely, though it’s not believed to be a season-ending ailment.Florida State (16-12, 7-10) has lost back-to-back games and will aim for only its third road victory this season.Duke, already without injured reserve post player Maliq Brown, apparently will be minus Proctor for the Florida State game. Proctor, who led the Blue Devils in scoring in three games in February, reached 1,000 career points before exiting in the first half Tuesday.So there could be a heightened role for freshman Isaiah Evans, who has had a recent uptick in production and started the second half of the Miami game.”Isaiah has established himself with what he has done,” Scheyer said. “It’s easy to talk about the shooting. His defense has been off the charts. He’s guarding the ball as well as anybody.”Evans made five 3-pointers in the first half Tuesday. In the last three games, he’s averaging 16.7 points and has shot 13-for-19 on 3-pointers.”You’ve just got to trust yourself at the end of the day,” Evans said.