AUBURN, Wash. – The cat-quick Chicks Special Angel headlines the $54,000 Bank of America Emerald Championship Challenge on Sunday at Emerald Downs, but the defending champion might be hard-pressed to hold off the rapidly improving 3-year-old Bh Lisas Boy in the meeting’s marquee event for Quarter Horses. Ten horses qualified for the Championship Challenge in a pair of trials Aug. 23, and none was more impressive than Bh Lisas Boy, who set a track record for 440 yards while surging past Chicks Special Angel to win by a half-length in 21.492 seconds. Bh Lisas Boy is 7 for 11 in his career, with stakes victories at Sun Downs, Portland Meadows, and Arapahoe Park for owner and trainer Bill Hoburg. He’ll be ridden by Javier Matias, who is 7 for 13 in Quarter Horse races this season at Emerald and unbeaten in four starts on Bh Lisas Boy. Chicks Special Angel dominated the 2014 Championship Challenge, winning by 1 1/2 lengths as the odds-on favorite. The 7-year-old mare has won 16 of 26 starts and is 4 for 6 at Emerald. Her start in the trial two weeks ago was her first outing since January, setting the table for a peak effort Sunday. She’ll break from the inside post position. Bh Lisas Boy drew post 6. Flyin Lion, who captured the other trial in 21.712 seconds, is another leading contender, but Chicks Special Angel looms the one to catch. Key contenders Chicks Special Angel Horses breaking from the inside are 3 for 27 this year in Quarter Horse races at Emerald. Chicks Special Angel started from the rail in her trial, and after being pushed in at the break, she ran well enough to win on most days. If that was just a tune-up, she’ll be very hard to deny. Bh Lisas Boy Hoburg’s homebred has yet to find his ceiling, the trainer said. “Coming off the pace is kind of his MO,” Hoburg said. “I’ve never seen this horse win gate to wire yet, and he could be really good if he breaks and goes on with it.” Bh Lisas Boy would be the first 3-year-old to win the Championship Challenge. The previous winners were 6, 8, 7, and 6. Flyin Lion She’s run a bunch of big races in Oregon, including a romp in the 2013 Portland Meadows Fall Derby, and was highly impressive in her trial victory, coming home powerfully despite getting knocked sideways shortly after the break. Time for Jesse Lee A multiple stakes winner in Idaho, Time for Jesse Lee was an even third in his trial run. He’ll have a new jockey Sunday in Alejandro Luna, who has 40 career stakes wins at Los Alamitos, including three wins in the Grade 1 Ed Burke Million Futurity.