A field of 61 horses and riders took on Olaf Peterson Jr.'s challenging track with only six advancing to the jump off.
After an easy clear in his first round, Casady was the final rider in the arena, and he took advantage of the 10-year-old Dutch Warmblood's massive stride to shave seconds off the clock, coming through the timers in a blazing 42.831 seconds.
"Durango has a very big stride. To make the time allowed in the first round I left out strides in a lot of different places, so in the jump off walking nine I knew I'd probably get eight," Casady said. "He's a stallion, but now that I'm getting to know him I'm making him more like my buddy. We're starting to get to the point where we do this together."
Karrie Rufer and Morning Star Sporthorses' Georgie d'Auvray EC, who were the first pair to earn a jump off round, set the pace with a time of 43.009 for second place. Nicole Shahinian-Smith secured third place with Akuna Mattata, who is owned by Silver Raven Farms, after two clear rounds and a speedy jump off time of 44.666 seconds.
Rich Fellers is in red hot form at the Sonoma International CSI2*. He claimed his third win of week Friday afternoon in the $5,000 Alimend 1.40m Winning Round aboard Valor Farm LLC's Burghlington. The pair produced two lovely clear rounds, stopping the clock at 36.102 seconds.
The format of the Winning Round class allows for the top 10 horse and rider combinations to return for a jump off round. Faults from the first round carry over to the second round, where riders aim to achieve the fastest time.
Kaitlin Campbell earned second with her seasoned partner Rocky W after two clear rounds and a jump off time only slightly behind Fellers in 36.162 seconds. Katelyn Denby Edwards and Mountain View West Farm LLC's Kalina followed in third after stopping the clock on 37.515.