(CNN) Tyler Summitt had skyrocketed up the women's college basketball ladder, becoming head coach of Louisiana Tech University's team in his early 20s with lots of promise, and cachet from his pedigree as the son of legendary coach Pat Summitt.
Now, the younger Summitt is out of a job and "profoundly disappointed in himself."
He announced his resignation Thursday, explaining he was doing so "for engaging in a relationship that has negatively affected people I love, respect and care about most."
Summitt did not elaborate on the nature of that relationship, or with whom it was, but did say he hopes now "to repair" others with people close to him.
"I am heartbroken that my time has ended in Ruston," he said, referring to Louisiana Tech's home. "But because of my respect for the institution, it is best that I resign."
Louisiana Tech athletics director Tommy McClelland told reporters Friday that the university had begun an investigation into allegations of an improper relationship before Summitt resigned.
"Dr. (Les) Guice and I met with Tyler at 10 a.m. (Thursday) ... and at the conclusion of that meeting he offered his resignation, and we accepted," he said.
The 25-year-old Summitt married Anne Dennis Ragsdale, his high school sweetheart, on June 1, 2013, according to his official bio.
Louisiana Tech issued a statement on the resignation "effective immediately and for personal reasons" of its women's basketball coach over the past two seasons.
"The university has accepted his resignation and appreciates the contribution he has made to the growth and success of the Lady Techsters program," the school said.
Summitt grew up in Tennessee, where his mother emerged as one of the most successful and respected coaches in college basketball. There she won a record 1,098 games, more than any NCAA coach. Her women's teams won eight national titles and she was named the coach of the century in 2000.
She was diagnosed with Alzheimer's disease in 2011 and is now head coach emeritus at the Knoxville school.
Tyler Summitt spent two seasons as part of the University of Tennessee's men's basketball team, and also played a role in the Lady Vols' program from 2007 to 2009, a stretch that included two national championships.
After graduating, Summitt went on to serve two seasons as an assistant at Marquette University under Terri Mitchell.
He became Louisiana Tech's head coach in April 2014, hoping to turn around one of the sport's top programs after its first two ever losing seasons.
His record in two seasons leading the Lady Techsters was 30 wins and 31 losses. Summitt had just completed the second season of a five-year contract.
Pat and Tyler Summitt through the years
Tennessee Lady Volunteers head coach Pat Summitt cuts down the net with help of her son Tyler after winning the national championship in March 1997.
Tyler Summitt attended his first basketball practice when he was 8 days old; he was 2 weeks old when he went on his first road trip. Here, his mother, Pat Summitt, burps him while giving pregame instructions to the Tennessee Lady Vols.
Pat Summitt is the winningest basketball coach in NCAA history. In Tyler's first year on Earth, the Lady Vols won the national title in 1991 and were honored by President George H.W. Bush at the White House.
Pat Summitt was 43 before she received a hug from her own father. She made sure her son always knew her love for him, hugging him often.
Pat Summitt tried to steer her son away from coaching, but she tells CNN: "I guess inside I always expected he would want to coach."
Tyler Summitt says his favorite memories with his mom were ones away from basketball, when he got more alone time with her.
Tyler Summitt gave soccer a try, but eventually his love of basketball took over.
Tyler Summitt meets his second president. Bill Clinton invited the Lady Vols to the White House in October 1997 after they won the national title in the spring.
When Pat Summitt began, she had to wash her team's uniforms, drive the team van and play in rec gyms. Her success changed the landscape for generations of women basketball players. She and Tyler cut down the nets after the 1997 championship.
The 1998 Lady Vols are considered one of the greatest teams to ever take the court, going 39-0 and winning a third straight national title.
Tyler Summitt crosses his arms and scowls while he observes a game against Connecticut in 1999.
Among the perks of the Tennessee Lady Vols winning national titles were the trips to Disney World.
Pat Summitt included Tyler in everything, from practices to road trips to autograph sessions.
A whistle around his neck, Tyler watches a summer camp with his mom. Of his new coaching job, Pat Summitt tells CNN: "He has the drive and has embraced the work ethic it will take to be successful."
"Tyler developed a love for the game and became a student of the game very early in his life," Pat Summitt says. Here, they celebrate with former Tennessee great Candace Parker at the 2004 Naismith Award banquet.
Although Tyler has met presidents and stars like Jay Leno, Pat Summitt raised him to be humble and true to his roots. "Be yourself," she tells him.
Pat Summitt stepped down at the end of the 2012 season after being diagnosed with early onset Alzheimer's. She and Tyler founded the Pat Summitt Foundation to assist in finding a cure for Alzheimer's.
In 2011, Pat Summitt was named Sports Illustrated's Sportswoman of the Year, an honor recognizing how much she changed the game. She finished her career with eight national titles and 1,098 victories -- the most ever for a collegiate basketball coach, men's or women's.
Tyler Summitt played on the male practice squad against his mother's team his freshman year of college. He also played on the University of Tennessee men's team.
Pat Summitt always emphasized academics with her son. The day he graduated from college was one of her proudest. He says he always loved looking at the banners in the arena signifying the hard work of his mom's teams.
Pat Summitt poses for a photograph with Tyler after she received the Arthur Ashe Courage Award at the 2012 ESPY Awards.
Tyler and his wife, AnDe Ragsdale Summitt, met in sixth grade and began dating their junior year of high school. The couple married on June 1, 2013. Pat Summitt speaks with AnDe about the rigors coaching can take on a marriage.
Tyler Summitt reaches for his mother after a press conference in April 2014 to announce Tyler Summitt as the new Louisiana Tech women's basketball coach in Ruston, Louisiana.
Tyler Summitt calls out to his Louisiana Tech players in December 2014 alongside associate head coach Mickie DeMoss, left, who spent two decades as an assistant at Tennessee under the his mother Pat Summitt.
In a 2014 profile, Summitt told CNN he was trying to forge his own coaching identity.
"I don't dislike the comparisons to my mom," he says. "I just have the ultimate respect for my mom."
She initially had tried to steer her only child away from wanting to work on the basketball court. She knew well the stress, the commitment, the days away from family. Her view changed with time.
"I guess inside I always expected he would want to coach," Pat Summitt told CNN. "I just hoped, like any parent, that he would find something he loved to do."
CNN's Wayne Drash and Steve Almasy contributed to this report.