Nichols Canyon and Shaneshill from the Willie Mullins stable will line up this evening against an American contingent headed by two-time winner Demonstrative for the richest-ever running of the Calvin Houghland Iroquois at Nashville’s Percy Warner Park (10.30pm).

The $200,000 Iroquois, the richest race on the National Steeplechase Association’s spring racing schedule, carries new significance this year as the kick-off contest for the 2016-2017 edition of the Brown Advisory Cheltenham-Iroquois Challenge which offers a $500,000 bonus to any horse that wins the Calvin Houghland Iroquois and the Ryanair World Hurdle at the Cheltenham Festival within a 12-month period.