HALLANDALE BEACH, Fla. &ndash; Leavem in Malibu, who was under consideration for the $16 million Pegasus World Cup, had to be euthanized following a Monday workout at the Palm Meadows training center after suffering a catastrophic injury to a hind ankle.Leavem in Malibu was galloping out following a five&#45;furlong breeze in 1:00.40 when he broke down on the backstretch, said trainer Mark Casse. Efforts to save the 5&#45;year&#45;old horse were futile.&ldquo;I&rsquo;m still in shock about it,&rdquo; Casse said Wednesday. &ldquo;It&rsquo;s extremely sad and unfortunate.&rdquo;Casse had intended to fill one of the 12 slots in the Pegasus with Leavem in Malibu. The second running of the Pegasus is set for Jan. 27 at Gulfstream Park, with entries due Jan. 24.Leavem in Malibu, an Ontario&#45;bred, was owned by Gary Barber and Conrad Farms. He won his last two starts, ending with the Grade 3 Valedictory last month on the Tapeta at Woodbine, bringing his career record to four wins from 12 starts and earnings of $326,412.As of Wednesday, 10 are confirmed for the 1 1/8&#45;mile Pegasus: Gun Runner, Collected, West Coast, Stellar Wind, Seeking the Soul, Sharp Azteca, Gunnevera, Toast of New York, War Story, and Giant Expectations. Gulfstream officials have said 12 will run.