Denny Harper and UC San Diego water polo will be forever linked. That's what happens after guiding the Triton men's and women's programs to 942 victories over 42 years. Harper's journey began under legendary coach, Flip Darr, at Rancho Alamitos High School. In his junior year in 1972, he began coaching the girls water polo team at Rancho and found his true calling. Afterwards he played two years at Santa Barbara City College for the coach he credits most for his education about the game, Dave Gray. Two years later it was on to San Diego State to finish his college career while launching his college coaching journey, leading the SDSU women's club team. Harper graduated in 1978; in the meantime, he went 130-18 with the Aztecs. In late 1979, fate intervened when best friend and former SBCC teammate Russ Hafferkamp asked Harper if he wanted to lead the UC San Diego men. It was a life-changing decision that turned a passion into a career. His four-plus decade run with the men's squad is nothing short of legendary. It includes 697 wins, 18 WWPA conference titles, 19 league Coach-of-the-Year selections plus a Guinness World Record for longest water polo game, clocking in at 26 hours. He also took the Tritons to the NCAA tournament 15 times, including a runner-up finish in 2000 earning National Coach of the Year honors.

In 1983 Harper was tapped to lead the UCSD women building the Tritons into a juggernaut, claiming five USAWP National Championship titles. Harper became the first coach to lead a women's team to a three-peat ('90-'92). Over his time in La Jolla, Harper navigated the Triton's transitions from non-scholarship Division III and then Division II to eventually Division I. Outside of college Harper stayed busy, coaching at two Olympic Festivals, first as assistant coach under Rick Jones in 1990 and then as the head coach in 1993 for the west women, with two gold medal results. In 1976, Harper founded the Sunset Water Polo Club. He coached the men to three Indoor National club titles and women to multiple senior national championships including an undefeated indoor/outdoor National Title winning streak between 1993 and 1997 as well as several Masters Nationals medals. In 2008 he joined forces with the Olympic Club of San Francisco, coaching the men's masters' teams and winning World Masters five times, most recently in 2023 in Japan.

Across his storied career, Harper received many accolades including induction into the UCSD Hall of Fame and a Lifetime Achievement Award from the ACWPC. Harper remains a supportive and influential fixture at UCSD Triton water polo matches and when not on the deck, he is spending time in San Diego with his wife Jefi, five children, two granddaughters and five golden retrievers.