The closest finish to the Aintree Hurdle since the famous dead-heat between Monksfield and Night Nurse in 1977 was a memorable centrepiece to the opening day of the Grand National meeting here on Thursday, as Impaire Et Passe, Bob Olinger and Langer Dan flashed past the post with just a nose and a short-head between them.

The drama also continued after the race, as Impaire Et Passe, the even-money favourite, had to survive an extended stewards’ inquiry into possible interference on the run to the line. Willie Mullins’s gelding was eventually confirmed as the winner, however, giving the trainer a Grade One double on the day and a useful boost in his late challenge for the National Hunt trainers’ championship.

“I thought the overhead angle was very revealing and that gave us a great chance,” Mullins said. “When Paul [Townend] went past Harry [Skelton, on Langer Dan] after the last there was never any interference there and I thought it was going to be very hard to disqualify us at that stage.

“Paul thought he was idling in front, and I think that was a legitimate excuse as well, but it will be interesting to hear how it went with the stewards.

“To get him back in a Grade One, and a race of this magnitude, was fantastic after his last two runs.”

Mullins was the only serious ­contender for the title to have a Grade One winner on the card, adding nearly £250,000 to his prize-money total for the campaign, but Paul Nicholls’s Sans Bruit took the £56,000 first prize in the Red Rum Handicap Chase later on the card and the defending champion remains favourite to hold on to his title.

Gordon Elliott, meanwhile, landed the Grade One feature over jumps, as Gerri Colombe, the runner-up behind Galopin Des Champs in last month’s Cheltenham Gold Cup, fought his way past Ahoy Senor in the closing stages to land the William Hill Bowl.

“Jack [Kennedy] said he was never happy with him the whole way,” Elliott said, “but it shows the goods the horse has.

“ I actually think he’d be a bit better on better ground, but it will be all systems go for the Gold Cup next year. We’ll probably go the same route again and keep dreaming.”

Elliott has eight runners, nearly a quarter of the field, in Saturday’s Grand National, and feels that Delta Work could prove to be the pick of his team.

“To be honest, the ground’s probably gone against a few of them,” Elliott, who hopes to become only the fourth trainer to win the race four times, said. “Chemical Energy and Galvin would probably want better ground. Delta Work and Coko Beach will probably love the ground.

“I’m really happy with Delta. I’ve probably not had him moving and working this well in the past few years.”

The first contest of the meeting over the Grand National fences was won by the 3-1 favourite, Its On the Line, at the end of a race in which 10 of the 22 runners completed the course.

All horses were reported uninjured afterwards, but Ben Sutton, who was a faller on Drop Flight, was taken to Aintree hospital for treatment while Harry Myddelton, who was unseated from Gaboriot, was reported to be under assessment at the track.

Protektorat can plunder top prize

Nicky Henderson enjoyed a welcome Grade One winner on the first afternoon at Aintree when Sir Gino took the juvenile hurdle, but another of his stable stars, Jonbon, faces a very tricky assignment against Dan Skelton’s Protektorat (3.30) in the Melling Chase at Aintree on Friday.

Jonbon was pulled out of the Champion Chase at Cheltenham last month on the same day that Shishkin – who finished fourth in the Bowl on Thursday – was scratched from the Gold Cup. Like most of the stable’s intended runners at the meeting, he did not show obvious signs of an infection when scoped, and has presumably been giving his trainer the right signs in the four weeks since.

He is attempting to bounce back from an odds-on defeat in January, however, and stepping up to two-and-a-half miles for the first time against two specialists at the trip in Protektorat and Pic D’Orhy.

Protektorat in particular promises to be a stern opponent, and while he has a couple of pounds to find with Jonbon on the ratings, his proven form over course and distance should give him the edge at around 3-1.

Aintree 2.20 It is a slight surprise that Making Headway has been dropped 1lb after a decent start to his handicapping career in the Imperial Cup and this step up in trip should suit.

Aintree 2.55 The choicely-bred Mystical Power, by Galileo out of Annie Power, went down only narrowly in the Supreme last time and can confirm the form with the third horse home, Firefox.

Aintree 4.05 Shakem Up’Arry is in the form of his life and while he narrowly missed out on a run in the Grand National, this assignment may well prove more suitable.

Aintree 4.40 This sharper track should play to the strengths of The Jukebox Man after he was caught in the shadow of the post at Cheltenham.