(Reuters) - Tiger Roll wrote his name into Grand National folklore with a second successive victory at Aintree on Saturday -- the first horse to claim back-to-back triumphs since Red Rum 45 years ago.

I Am Maximus, the easy winner of the Grand National last year, will need to emulate a feat last achieved by the mighty Red Rum if he is to double up at Aintree on 5 April after he was allotted top ...