Twenty-one day ban rules Hills out of Guineas
Hills was found guilty of failing to ride out to the line on the John Dunlop-trained Buthaina, who dead-heated with Swift Alchemist in the Sponsor At Newcastle Median Auction Maiden Stakes.
Buthaina wore down the eventual third Jordans Elect in the closing stages, but Swift Alchemist, racing on the opposite side of the course, forced a share of first place.
Hills' mount started at 11-8 favourite and punters lost half their possible winnings and half their stake on the filly because she did not win outright.
Stewards' secretary Phil Tuck said: "The stewards felt that Richard had failed to ride out approaching the finish, therefore forfeiting outright first place."
Hills had been due to partner fancied contenders Khulood in the Sagitta 1000 Guineas and Muqbil in the Sagitta 2000 Guineas, and he was clearly upset by the decision.
He said: "I will have to speak to Michael Caulfield (chief executive of the Jockeys' Association) and consider appealing.
"I had rides with good chances in both the Classics and then there is Chester and York. It is just a bit of a shock at the moment."
Before learning of the length of his suspension, which runs from May 1 to 10 inclusive and May 12 to 22 inclusive, he reasoned: "I did not stop riding. I was just getting up from the drive position. It had taken my horse two furlongs to get past Jordans Elect. I can't believe this is happening."
Meanwhile Mick Channon and jockey Steve Drowne stole the show with a sparkling treble from Pivotal Guest, Black Falcon and Analyze.
The duo set the ball rolling when Channon got off the 13 mark for the season when Pivotal Guest just got the better of the gambled-on Imperial Echo in the Racecourse Video Services Maiden Stakes.
Imperial Echo was backed from 7-1 to 11-4 favourite and gave his supporters a good run for their money, but after a sustained battle he was a head adrift of Pivotal Guest where it mattered.
The winner carries the colours of John Guest, whose racing manager Tim Corby said: "The penny did not drop with him until the last half-furlong and I am sure there is a lot of improvement in him."
Channon and Drowne doubled up when Black Falcon won the Thank You To The Racecourse Doctors Maiden Stakes in impressive fashion, and the jockey said: "He has come on leaps and bounds since his first run he quickened up well when I pressed the button, and I think there is still a bit of improvement in him."
The trainer jockey combination completed the treble when Analyze produced a telling late burst to land the concluding Thank You To The Racecourse Vets Handicap.
Trainer Steve Gollings made the long trek across country to Wales pay dividends when Castleshane dominated proceedings to lift the Wendy Fair Markets Showcase Handicap Hurdle under Tom Scudamore at Chepstow yesterday.
Gollings boasts a formidable strike rate at the Welsh circuit and has now sent out three winners from just five runners over the past five years following Castleshane's all-the-way 10-length verdict over Murray River.
The trainer said: "This is quite a lucky track for us as Springfield Scally also won a valuable hurdle for us earlier this season, which is a good job really as it's a hell of a long haul from where we train.
"It's a big plus point for the horse when he can dominate a race like he did there. He ran in the County Hurdle at Cheltenham last time and probably sulked a little when he could not get to the front.
"I suppose I will have to look at something like the Swinton Hurdle at Haydock for him now and after that he will go back on the Flat this summer as he also seems to like running around Chester."
Paul Nicholls clocked up his 149th winner of the season when Iverain, ridden by Joe Tizzard, had little problem disposing of sole rival Far Dawn by six lengths in the Robert Hughes Novices' Chase.
Nicholls' assistant Jeremy Young said: "We set a target of 150 winners and £2million in prize money for the season when we saw it was possible and as we've sealed the latter it would be nice to get the winners.
"We haven't got any runners tomorrow but will have a few at Perth at the end of the week and of course for the big meeting at Sundown on Friday and Saturday, so we are hopeful of getting that remaining winner."
Venetia Williams saddled Knocktopher Abbey to open his jumping account when taking the Hills Group Maiden Hurdle in the hands of Brian Crowley. The six-year-old had nine lengths to spare from Sturm Und Drang.
