Ryan Kelly injured his right foot in Duke’s easy win last night over Clemson and didn’t play at all during the second half. Mike Krzyzewski noted that Kelly would not undergo x-rays or any other scan until today. So here are the bald facts: Ryan Kelly hurt his foot and we have no idea how badly it is injured. He’s hurt this foot before. Right now, anything beyond this is just in the realm of speculation. Kelly could very well be perfectly fine at the moment of this publication. However, if the injury is serious and Kelly misses significant playing time, this could also be a serious blow — a season-changing one — to the top-ranked Blue Devils.
During his tenure at Duke, Kelly’s ability to play stretch power forward has been a difficult match-up for just about any team in college basketball. This year, the 6’11” Kelly has made over half of the nearly 50 three-pointers that he has taken. He leads his team in offensive efficiency, rarely turns the ball over, and is an excellent passer for his size. He’s a good (though not great) rebounder, and his ability to get to the foul line on a regular basis and shoot a high percentage from there has given his already versatile offensive game another deadly dimension. While early in his career Kelly was often criticized for poor defense, the vastly improved senior has helped lead the team to a top-three mark this season in defensive efficiency. The long story made very short is this: Kelly is really good.
Plus/minus is one of the most debated statistics in basketball, a theoretically simple measure of how the score changes when the player is on the court. It is in practice, though, confounded by any number of complicating factors. Substitution patterns, pace, quality of opponent and other things can throw off plus/minus and make a comparison between players across teams nearly futile. For comparing players on a single team, however, the metric has its use. No player on Duke has more positively affected the score than Kelly. When he’s on the court, the Blue Devils increase their lead. Again, take this with plenty of grains of salt, but currently Ryan Kelly leads the entire conference in total plus/minus and average plus/minus.
Unfortunately for Duke, one of the reasons that Kelly so positively impacts the game is because his back-ups have not played very well. Josh Hairston, Amile Jefferson, and Alex Murphy are the three worst offensive players on the team who see significant minutes, with none posting an offensive efficiency above 100. As a point of reference, Kelly’s offensive efficiency rating before Tuesday’s game was 126. In practical terms, using any one of these three players in Kelly’s spot is liable to cost Duke something like 26 to 34 fewer points per hundred possessions. Duke’s offense loses a big part of its scoring punch without Kelly on the floor.
Still, the end of Duke’s big man rotation has its own strengths. It’s possible that Duke will be even better defensively with those three seeing more minutes. Jefferson and Murphy are still unseasoned and developing on the court, and both are likely to get a lot better. Even with one of these players taking Kelly’s spot as a starter, Duke is still an excellent team across the board. The emergence of Quinn Cook and the renewed brilliance of Mason Plumlee and Seth Curry gives teams more than enough to worry about in terms of defending the Blue Devils. If Kelly ends up missing a significant amount of time, Duke will still win games, but the team will clearly be worse for wear.
Again, there is a good chance that Kelly is perfectly fine. If the foot injury turns out to be more serious, however, the Blue Devils will acutely feel Kelly’s absence for however long he is out of the lineup.