Bobs Worth got back on track after a below-par run on his seasonal debut to land the Grade One Lexus Chase at Leopardstown.

Winner of last season's Cheltenham Gold Cup, Bobs Worth could finish only sixth behind Cue Card in the Betfair Chase at Haydock, but Nicky Henderson felt the course was too sharp for him.

The champion trainer was convinced Leopardstown would be more suitable, although he was concerned about the ground, but he was vindicated as the eight-year-old showed once again he is a top-class staying chaser.

First Lieutenant jumped the last in the lead, but Bobs Worth (11-4 joint-favourite) found plenty for Barry Geraghty on the run in to win by a length-and-a-half, with Rubi Ball back in third.

The victory put Bobs Worth right back into the Betfred Cheltenham Gold Cup reckoning. RaceBets.com, Betvictor and Paddy Power all make him the 5-2 favourite to retain his title.

And it capped a rollercoaster 24 hours for Henderson whose treble at Newbury yesterday - Captain Cutter proved the highlight in the £35,000 Betfred Goals Galore Challow Novices' Hurdle - came after he suffered a major blow on Friday when Sprinter Sacre was pulled up with an irregular heartbeat on his reappearance at Kempton. Henderson said yesterday: "Sprinter Sacre went to Newmarket first thing this morning following a night spent at home where he ate up and was perfectly sound this morning.

"Following initial cardiac examination by Celia Marr, she has confirmed the diagnosis of the racecourse vets and he does have an irregular heartbeat, which is known as atrial fibrillation.

"What she would like to do is wait for a further 48 hours to see is this will stabilise on its own. If not, medicines and technology will come into employment."

Denman is a recent case of a top National Hunt horse recovering from a similar problem. The 2008 Gold Cup hero had an operation to correct a problem that September and although he was beaten on his return the following February, he was capable of finishing second to Kauto Star back at Cheltenham and winning the Hennessy a few months later.

"This is apparently virtually identical to the situation that Denman went through," added Henderson.

"In her [Marr's] opinion the reason for these situations is that both horses are supreme athletes and they are more likely to suffer from these problems due to the size of their hearts, which in both cases are unusually large.

"Because of the muscle density around the heart, it can cause this situation."

The diagnosis, however, failed to dampen Henderson's delight over Bobs Worth's victory, which came six weeeks since he lost at the same venue.

"I would have given anything to take him out two days ago. With the ground and the weather, I wasn't that happy with him, but the horse never stops surprising you," said Henderson.

"You have to be handier round here than you would normally be. When I saw Barry angle him out, I said to myself obviously he thinks he'll get there. We all know he finishes his races, except of course for Haydock.

"I wanted to wait for the Argento Chase [at Cheltenham on January 25] but Barry was keen to come here. He believed he would get better ground here than anywhere in England.

"If we waited for the Argento and it turned up heavy, we'd only have five or six weeks before Cheltenham. This was the right race for him but conditions weren't perfect. He picked himself up after a horror run and he put himself back at the front of the ball game."

Geraghty, who also steered Denis Cullen's Dysios (8-1) to victory in the Star Best For Racing Christmas Rated Hurdle, said: "He's brilliant, he's got great heart. He didn't get his ground in the Gold Cup and he showed his pace today. He's a better horse on good ground."