Krystkowiak cited extracurricular incidents in two of the last three meetings between the two teams most recently, BYU's Nick Emery punching Utah guard Brandon Taylor in the late stages of the Utes' 83-75 victory over the Cougars at the Huntsman Center last month.
"The events that have occurred in our recent games with BYU led me to ask Dr. Hill several weeks ago if we could take a cooling off period and put the rivalry on hold," Krystkowiak said in the statement. "The level of emotions has escalated to the point where there is the potential for serious injury."
Neither Krystkowiak nor Hill were available to take questions from the media after acknowledging that Utah's most-played rivalry and the seventh-most played rivalry in college basketball will be on hiatus.
BYU coach Dave Rose, clearly unhappy about the cancellation, called Krystkowiak's cancellation request a first in his coaching career.
"I was very surprised. Shocked, actually," he said. "I have been doing this for 32 years in high school, and junior college, and now the Division I level, and we've had hundreds of agreements on games verbal agreements, handshake agreements, contractual, written contracts. And this is the first time that I've had one not fully executed."
Rose also disagrees with Krystkowiak's contention that the series needs a cooling off period.
"Well, the rivalry is pretty heated," he said. "We've had some interesting moments over the years. I have been involved in it for 18 years, and that's a lot of the excitement of the game, is, you don't want things to get out of hand. But in rivalry games things tend to get pretty heated at times. I don't think, from my point of view, that the safety of the players is an issue."
The series stands almost dead even through over a century of games: Since 1909, BYU has 129 wins to Utah's 128. The Utes have won the last three games all sellouts in both Salt Lake City and Provo. But the most recent meeting was dominated by Emery's punch, putting the Utah crowd on its feet and sending a furious Krystkowiak from the bench onto the floor. The sparks continued on social media, where Utah and BYU fans sparred overnight and into the next day about the circumstances and cause of the incident.
It was BYU's second ejection in three years against Utah: Cougar center Eric Mika was ejected in 2013 for a flagrant foul hit against the Utes' Dallin Bachynski. The series history is filled with chippiness and physicality in 2010, then-Ute Marshall Henderson was ejected for striking BYU's Jackson Emery as many rivalry series are. But with the teams in different conferences, the cancellation of the series hasn't been on the table until recent years.
While Krystkowiak initially seemed to warm to the fire of the Utah-BYU rivalry, memorably donning a red blazer in each of the last two games, his Wednesday comments marked a shift in his sentiment. And Utah AD Hill is backing his coach while leaving the door ajar for a resumption of the series down the road.
"In the interests of our student-athlete welfare, [Krystkowiak] requested we cancel the BYU series until further notice," Hill said in his statement. "Given his reasons, I agreed to cancel next year's game. We will revisit resuming the rivalry at some point in the future."
That may be a tough sell for Rose and the Cougars.
"It is scary, because how do you put another contract together? Another agreement together? So, that's how I feel," said the BYU coach who added that if a new series is ever agreed to, it will include "a much larger buyout."
With next season's game against BYU now cancelled, the Utes moved a littler further away from their longest tenured in-state rivalries. The program hasn't played Utah State since 2010, and Weber State since 2011.