Irish amateur Declan Queally accused English jockey Nico de Boinville of "abusing" him before the Turner Novices' Hurdle.
The opening race on day two at Cheltenham started almost four minutes late after a prolonged effort to get the 21 runners into a suitable order, with De Boinville and Queally clashing as they fought for a position close to the tapes.
Returning to the weighing room following the race, Queally, whose mount I'll Sort That finished fifth, told ITV Racing: "The start was a bit of a mess and I got trapped back further than I wanted.
"I was being abused by an English rider, Nico de Boinville, and it's not very nice. I'm an amateur coming here riding in front of my kids and that, it's horrific."
Riding runner-up Act Of Innocence, De Boinville - who won the Gold Cup aboard Coneygree in 2015 - responded: "Maybe he should look in the mirror."
Queally lodged a complaint following the incident, and stewards have adjourned the matter to gather more evidence.
On Thursday, the stewards said further evidence will be gathered over the "coming days" after the Cheltenham Festival, with information collated and considered via the stewarding process or referred to the BHA's head office.
Queally was also one of four jockeys found to have breached the rules at the start of the race by the stewards and has been given a one-day suspension.
A report read: "The starter reported that Jack Kennedy, the rider of Ballyfad, Mr D. Queally, the rider of I'll Sort That, Danny Gilligan, the rider of Skylight Hussle, and Darragh O'Keeffe, the rider of Walks In June, had not approached the tape at a walk or a jig-jog thereby causing a false start, resulting in a standing start."
Analysing the start on ITV, riding greats Ruby Walsh and Sir Anthony McCoy felt both riders had the right to stand their ground, with Walsh reiterating his stance that the starting procedures require alteration.
McCoy said: "One person has as much right to be there as someone else. Just because whoever you are doesn't mean to say you should be in there. I don't think Declan's done much wrong. I don't think one person is any more entitled to be there than another."
Walsh added: "That's the same Nico de Boinville who rode Jonbon last year and put his head on the tape. Maybe he needs to look in the mirror, too. You need a rolling start.
"I've said it for a long time, if they walk in front of a tape and then it moves in front of the horses, you'd have none of this drama."
