The Kentucky Oaks undercard at Churchill Downs featured two milestone graded stakes wins for under-the-radar sires in Country Day and Tizway. Backyard Heaven’s win in the Grade 2 Alysheba Stakes was the first graded winner for his sire, Tizway, who now resides in South Korea. Backyard Heaven is $31,826 from becoming Tizway’s leading North American-based earner. That honor belongs to Coasted, who won the listed P.G. Johnson Stakes, finished second in the 2016 Breeders’ Cup Juvenile Fillies Turf, and hit the board in two Grade 3 races. The global leader is Buhwarui Banseok, who has made $455,288 racing in Korea. Tizway, a 13-year-old son of Tiznow, has sired four crops of racing age, with 129 winners and combined progeny earnings of more than $8,229,134. His other runners of note include graded or group-placed runners Our Way, Gran Vanessa, Bear’sway, Malibu Stacy, and Tizzarunner. On his own accord, Tizway won 7 of 20 starts for $1,359,274, highlighted by victories in the Grade 1 Whitney Invitational Handicap and Metropolitan Handicap, as well as the Grade 2 Kelso Handicap. Tizway entered stud at Spendthrift Farm in Lexington, Ky., for the 2012 breeding season and resided there until the end of the 2017 season, when he was sold to stand in Korea. Will Call’s mild upset in the Grade 3 TwinSpires Turf Sprint Stakes was the first stakes win of any kind for his sire, Country Day, who stands privately at Crestwood Farm in Lexington, Ky. Klein Racing campaigns Will Call as a homebred, the same as it did Country Day, a son of Speightstown who was a Grade 2-placed stakes winner. He ran second to Regally Ready in the 2011 Breeders’ Cup Turf Sprint at Churchill Downs. Country Day has sired three crops of racing age, with 18 winners and combined progeny earnings of $912,385. Will Call accounts for $232,521 of that total. Also earning six figures for Country Day is Top Player, a 4-year-old gelding who has raked in $106,707. ◗ Two-time Horse of the Year Curlin continued his streak as one of the most consistent stamina sires in America with champion Good Magic’s runner-up effort in the Kentucky Derby, as he has now produced a classic winner or classic-placed starter from each of his six crops to race. Curlin was represented by 2013 Belmont Stakes winner Palace Malice in his first crop. He was followed by 2014 Preakness Stakes runner-up Ride On Curlin, and Keen Ice, third to Triple Crown winner American Pharoah in the 2015 Belmont. Exaggerator won the 2016 Preakness after finishing second in the Kentucky Derby. Last year, Irish War Cry finished second in the Belmont. – additional reporting by Nicole Russo