Cash is King Stable managing partner Chuck Zacney, co-owner of Afleet Alex, announced Tuesday he has accepted Dan Borislow's $50,000 challenge matching Borislow's Wild Desert against Afleet Alex and Rockport Harbor in a horse-against-horse showdown in the April 16 Arkansas Derby (gr. II).Borislow's challenge was issued by Philadelphia sports personality Keith Jones, who owns 3% of Wild Desert, on Jones' radio show Tuesday morning. The Philadelphia-born and raised Borislow, who said he would donate his winnings to charity, offered to bet $50,000 that Wild Desert would finish ahead of Afleet Alex and Rockport Harbor, both of whom are also owned by Philadelphia area natives."We always welcome a challenge," Zacney said through Cash is King representative Anita St. Clair. "I would put a healthy Alex against any other 3-year-old and will take my chances. I believe you will see the old Alex (in the Arkansas Derby), the one with five wins and two seconds."Zacney was referring to Afleet Alex's last-place finish in the Rebel Stakes (gr. III), in which he was suffering from a lung infection, which has since cleared up.St. Clair said Zacney would donate his winnings to "Alex's Lemonade Stand" and his own church, St. Mary's in Phoenixville near Norristown, Pa. Zacney became aware of a young girl suffering from cancer named Alex who had opened a lemonade stand to raise money for cancer research. Zacney felt the bond between the two common names and pledged $5,000 to Alex's lemonade stand. Although the young girl has since passed away, Zacney remained committed to her effort, and continues to donate a portion of Afleet Alex's earnings. To signify his support, all of Afleet Alex's gear is emblazoned with a lemon, and a portion of those proceeds are also donated to Alex's Lemonade Stand. The hope is to open a lemonade stand at Churchill Downs.There has been no word from Rockport Harbor's owner Rick Porter, with the colt's status for the Arkansas Derby in question due to a blood clot and infection.