'She's an intriguing filly and I'm not convinced she is exposed yet' - who has a fancied runner at Killarney?

There is a possibility a smart stayer could stamp their authority at Leopardstown in the Listed Vinnie Roe Stakes (6.55) as several unexposed-three-year-olds tackle the 1m6f trip.

Most eyes will be drawn to Waltham, who seems a colt of immense promise after only two starts. He is 2-2 at this track on varying types of ground and his six-length victory in a conditions race last month marked him out as a talented prospect.

He does have some similarly unexposed sorts to master, including the Aidan O'Brien-trained Alexandroupolis, who is making his belated return to action after finishing third behind White Birch in the Ballysax last April, while Harbour Wind is stepping up markedly in distance for Dermot Weld after an impressive Navan victory.

The first of a three-day festival kicks off at Killarney and the Listed Vincent O'Brien Ruby Stakes (5.30) is shaping up to be an intriguing race. Comhra is taking a marked step in grade having run Group 1s, but Cosmic Vega is a worthy challenger for Michael Halford and Tracey Collins.

The five-year-old won at this level at Naas in May and wasn't beaten far into fifth in a strong Group 2 at Leopardstown before finishing third in testing conditions at Cork last Friday.

Joint-trainer Michael Halford said: "We're looking forward to a big run. On ratings, Jim Bolger's filly looks the one to beat along with maybe Aidan's. He is a course-and-distance winner and has come out of his run at Cork last week in really good form."

Richard O'Brien saddles two interesting runners from his Limerick stable in the Kingdom Gold Cup Premier Handicap (7.10) over 1m6f later on the Killarney card. Last Ammo caused a 40-1 upset when landing a handicap over 2m½f at the Galway festival and has been given a 14lb rise, and Marvelosa was beaten less than a length into third at the Curragh last weekend over 1m4f and could be ideally suited to this trip.

Richard O'Brien said: "Last Ammo was terrific in Galway. He is coming back in trip and is up a stone in the weights, so there are a couple of unknowns. The two miles suited him the last day and if I had a choice I would probably be going up in trip rather than back in trip, but there's nothing else for him until the middle of next month.

"I think if he came in the first five, it would be a solid effort. There's a Cesarewitch trial at Newmarket next month that he could go for, all being well.

"Marvelosa ran well at the Curragh last weekend but I think that trip is on the short side for her. She's an intriguing filly and I'm not convinced she is exposed yet. She is well drawn and Sean Bowen is taking a valuable 7lb off, so I'm looking forward to seeing her."

Read our Thursday previews:

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