The race to be crowned the best two mile novice chaser just opened right up this week after it was revealed that Arkle Trophy favourite Le Richebourg has been ruled out of the Festival following an injury on the gallops.

The setback now effectively ends the campaign for JP McManus’s six-year-old gelding, trained by up-and-coming star handler Joseph O’Brien, and it is a major blow to both parties after Le Richebourg hit the head of the Arkle market having notched four wins in five chase starts this term including two Grade One wins in a row.

His wins in the Racing Post Novice Chase and the Irish Arkle, both at Leopardstown, had marked him out as the clear number one contender for the famous race after some disappointments for other contenders, most betting firms going no bigger than 5/2 about him in advance of the race.

O’Brien reported that, despite having worked normally on Saturday morning, he wasn’t happy with him afterwards and upon further veterinary investigation found him to have collected an as yet unspecified injury that now finishes his season prematurely, albeit it’s still been a very successful one.

It may not be all bad news for Joseph O’Brien in the context of this race though, as following Le Richebourg home in both of his Grade 1 successes was stable companion Us And Them meaning if the form really was that strong, he may yet have a contender after all.

Us And Them however is a general 20/1 shot with previous ante post jolly Lalor now moving back to the head of the market at around 3/1 with most firms.

Kayley Wollacott sent the seven-year-old to Exeter for a racecourse gallop under champion jockey Richard Johnson on Saturday which is said to have gone very well and the German-bred gelding has already shown a liking for the track having taken the Arkle Trial in impressive fashion at Cheltenham back in November.

Prominent owner JP McManus is also not fully out of luck in this contest by the way, as right near the head of the betting is his Defi Du Seuil who landed the Scilly Isles Novices’ Chase (Grade 1) at Sandown at the beginning of February and is right on track for the race.  The French-bred of Philip Hobbs’ yard is as short as 3/1 in places.

The last real conundrum for punters to tackle is the form line featuring Kalashnikov and Glen Forsa.  Amy Murphy’s stable star had been vying for favouritism in this race at the start of the season, but came unstuck the last twice in the Wayward Lad and Kingmaker Novices’ Chase with many feeling he’s now out of it.

In the latter, Mick Channon’s Glen Forsa took a huge step forward to slam Kalashnikov by 19 lengths earning him a higher ranking in the betting at a general 7/2 versus 10/1, but that could be a narrow-minded view in all honesty.

As good as Glen Forsa was that day, there’s no doubt that Kalshnikov was not at his best and as a very narrowly beaten second in last season’s Supreme Novice’s Hurdle he has crucial Cheltenham Festival form which can count for plenty when things get rough on the big day.

Whatever happens it’s a shame that one of the most promising chasers out there cannot run in the shape of Le Richebourg, but this race is still chock full of quality and whatever wins it will need to put in a superb round of jumping.