Days before Duke was scheduled to depart for a trip to the Dominican Republic, the school announced Thursday afternoon that Hall of Fame coach Mike Krzyzewski needs right knee replacement surgery. Because of this, the trip is off. Krzyzewski will undergo surgery this weekend at Duke University Hospital. 

Duke posted this video on Twitter, and in it Krzyzewski vows to be at "full speed" in time for the official start of practice at the end of September. 

This surgery marks the second major for for Krzyzewski in 2017. He underwent back surgery in early January, which caused him to miss a month's worth of games. 

"Unequivocally, this is the absolute right thing Mike should do, and at precisely the right time," Duke athletic director Kevin White said. "Certainly, we know Mike will receive unparalleled medical care here at Duke, and that his recovery will lead him into his 38th season here at full strength. Once again, that is exactly what Mike, and our team, should do as we head into the 2017-18 season, wherein we are extremely excited to see what the upcoming year brings."

Duke is ranked No. 7 in the Top 25 (and one), but this team will be one of Coach K's youngest. Grayson Allen is the lone returning player who logged significant minutes last season. Duke is bringing in lauded freshmen Trevon Duval, Wendell Carter and Gary Trent Jr. It's also in the midst of an intricate recruitment of No. 1 2018 prospect Marvin Bagley, who is exploring reclassification to 2017.

If Bagley were to reclassify and select Duke, the Blue Devils would figure in the national-title favorites picture. Krzyzewski is preparing to enter his 43rd season as coach, his 38th at Duke.