Just over 90 seconds is all it will take. Ninety seconds across the windswept Newmarket heath and we'll know if King Of Kings is the classic colt of substance his fans insist he is or a hollow shell. The 2,000 Guineas will be the proof - simply because there will be nowhere to hide.
Since his awesome racecourse debut over 11 months ago, today's race has been King Of King's destiny. Now he must put up or shut up. And what a put up it will be. Not only has King Of Kings to overcome a suspect temperament which could easily see him boil over in the preliminaries, there is also the suspicion that his courage may not be commensurate with his natural talent.
After his Curragh debut, bookmakers hands were chewed to the marrow as the faithful snapped up 2,000 quotes of 25/1 and that was on May 25th, 1997! Four more races, three of them victories, and that kind of certainty was never repeated. Yes he won a Group One but the question marks kept multiplying, principally around whether that head of his kept rising back into his jockey's lap because of greenness or a dilettante's hatred of hard work.
Racing's sceptics would normally plump immediately for the latter but then there is the fact that King Of King's trainer Aidan O'Brien is something of a genius. He is keeping the faith and that has prompted even more money to force King Of Kings' price down to a clear 7/2 second favourite.
Yesterday O'Brien said: "We are very happy with the horse and after working all Spring on the soft he should get decent ground for the first time at Newmarket. We nursed him last year and he was never asked a big question but the gun will be put to his head now."
Michael Kinane will be the man with his finger on the trigger but through the race surely the main figure in his sights will be Xaar, last year's brilliant two-year-old who returned to action with a comfortable win in the Craven over the course and distance last month.
Unlike King Of Kings he has the benefit of a run already and it also made Andre Fabre and Olivier Peslier aware of the one chink in Xaar's armour going into the Guineas.
In the Craven as well as last October's Dewhurst, there was a furlong in the middle of the race where the enviably laid back Xaar hit a flat patch and Peslier had to scrub him along before the colt hit the afterburners. Should the same happen today off a slow early pace, Xaar could find it difficult to make up the ground going into the dip. Apart from that, the little son of Zafonic looks virtually as bombproof as any Guineas favourite has ever been.
The contrast with his enigmatic Irish rival is clear. With Xaar, we know. With King Of Kings we're still in the dark.
Tomorrow's 1,000 Guineas sees Shahtoush go for O'Brien and the Moyglare winner Tarascon represents Tommy Stack who took this race with Las Meninas in 1994. Like that filly, Tarascon comes here without the benefit of a pipeopener this season but her juvenile form reads really well and ground will not be a problem. She looks a reasonable each way bet while the ground may be just drying out a little too quickly for Shahtoush to be seen at her best.
In contrast, Loving Claim loves to hear her feet rattle. As a Prix Marcel Boussac winner, Loving Claim's quality is proven and trainer Criquette Head has a wonderful 1,000 record.