Nate Chambers is up against six horse-and-rider combinations short-listed for this fall’s Alltech FEI World Equestrian Games, but he kept cool under pressure today at the Richland Park CIC***. Chambers and Rolling Stone II beat out those four-star challengers and plenty of other experienced pairs in the dressage on Thursday (45.9), and they maintained their lead today, Aug. 28, with a double-clear cross-country round in Richland, Mich.