Time To Stop Doubting Thomas What are we all to make of the Arc trials at Longchamp last weekend? It is fair to say that in the immediate aftermath of the Prix Foy, the big race itself looked quite straightforward.Manduro, at the time the highest-rated active racehorse in the world, conclusively proved that he would stay the mile-and-a-half trip of the Prix de l'Arc de Triomphe.The way he beat triple Group One-winning filly Mandesha with Stephane Pasquier not even having to resort to the whip had us thinking this beast could be the best we have seen since Dancing Brave.Because of the public's obsession with Derby winners forcing Authorized into an awfully short price, we could still back Manduro at around 7-2 ? surely buying money.However, racing is nothing if not cruel and it emerged an hour or two later that Manduro had run his last race ? a terrible blow for racing fans.The other significant trial saw Aidan O'Brien's Irish Derby winner Soldier Of Fortune prove he could handle quicker conditions with a comfortable success in the Prix Niel, a race used as a springboard to Arc success last year by Rail Link and many others before him.But the race had a distinct ?trial' feel to it. His main rival Zambezi Sun looked as big as a house and completely blew up inside the final furlong, with Johnny Murtagh allowed to steal the race from half a mile out (when will fellow jocks learn that Murtagh has no peers when allowed to dictate a race?).The fact that Ballydoyle ran eight in the Derby suggests there is nothing between the three-year-olds at home. And don't forget that Kieren Fallon even chose to ride Eagle Mountain in the Irish Derby, so much had Soldier Of Fortune been showing at home!It might just be that this year the three-year-olds are not that good, bar Authorized.He atoned for his defeat in the Eclipse by winning the Juddmonte International at York in fine style, beating the ultra-consistent Dylan Thomas.As the York race was over 10 furlongs, it was vital for Authorized's stallion career he gained a Group One win over the distance, but Dylan Thomas is seen to much better effect over a mile and a half.Throw into the ring that Authorized has never travelled abroad before, will have no experience of running at Longchamp, unlike his main rivals, and five of his six races have been on left-handed tracks.There are just too many imponderables there to get stuck into the 6-4 currently on offer. Dylan Thomas, however, has five wins at the highest level compared to Authorized's three and the 5-1 price about the Ballydoyle inmate looks huge.How he can be double the price of his stablemate Soldier Of Fortune when you compare their relative achievements beggars belief.Another deciding factor is that Dylan Thomas is the only horse to have given Manduro a race this season in the Prince Of Wales's Stakes at Royal Ascot, over the inadequate trip of 10 furlongs.All we need is good ground. Any rain at Longchamp beforehand would seriously scupper his chances.Admittedly, three-year-olds have ruled the roost in the Arc recently but the best of them all, Peeping Fawn, doesn't even look like she is going to be in the line-up so take a chance on the ground and get stuck into Dylan, who can give O'Brien his first win in the race.By Nick Robson, PA Sport