For a few extremely tense hours here yesterday there was increasing order and plenty of merit in the race to finish the season on top of the European money list. But then David Howell and Padraig Harrington lost ground almost as dramatically as they had made it up and Paul Casey was suddenly returned to overwhelming favouritism.
But if yesterday signified anything, it is that everything is possible at Valderrama.
The complexion of the day changed more than that of Casey has in the past few days; the young Englishman now pink again after being Kermit green in the outbreak of food poisoning that plagued the first two days here. There are casualties still being claimed - Jose Maria Olazabal, for example, was still on a drip in the locker room as his tee-off time approached - but with the bug seemingly running out of guts to occupy, it was Howell and Harrington who were left feeling the sickest. What chances they had given themselves to leapfrog the Order of Merit leader.
Indeed, when Casey finished off his 71 to lie at five-over and in 32nd place, the likelihood of his near £150,000 advantage being cosy enough was looking decidedly unlikely. At that stage Howell was only in the process of retreating from his march to the top of the leaderboard while Harrington was just speeding his up.
"There's not a lot I can do," Casey said, not so much resigned to a particular fate but fully prepared for any. "I'm going to be a spectator tomorrow, although I suppose if I play well I can make it harder for Padraig."
In fact, what Casey does in this final round could very well settle it. Harrington needs to win or come second to deny his 29-year-old rival, but with players of the calibre of Sergio Garcia, Lee Westwood and Henrik Stenson three shots ahead of him - who are in turn one behind the unheralded leader, India's Jeev Milkha Singh - the Irishman knows "it is some tall order".
Harrington might just fancy sneaking into third, however, but this is where Casey comes in. If he can stay in the top 35 then he would hang on. Just.
Howell and Robert Karlsson, meanwhile, must win or come second and at level par are still outside threats. But after seven holes yesterday, Howell was very much on the inside. At that stage he was at four-under, at the head of the field, and apparently striding clear after notching up his fifth birdie in succession on the treacherous seventh. But then came the eighth hole and if the wheels didn't fall off, the hubcaps rattled. "It was a case of momentum gone," he said. "I had an easy sand-wedge in, came up short and three-putted. I was in a nice little zone until that happened. After being five-under through seven it was obviously disappointing only to score 70, but I would have taken it before the start. Possibly."
Harrington bore a similarly unfulfilled expression after the putter jammed itself between the spokes to arrest his charge as well. On the 14th he was "going along very sweetly" on two-under, one behind the pace, when a series of bitter three-prods struck. The last left the ugliest taste, coming from just seven feet when a birdie was in the offing on the 16th.
"That probably cost me a birdie on the 17th as well as it really shook me," said the Dubliner who finished second in 2001 and 2002. "I will need to shoot five- or six- under to have a real squeak tomorrow. There's so many good players in front of me." As a Ryder Cup player, Harrington knows only too well how beneficial it might prove for Casey to have Garcia and Westwood on his side.
Nevertheless, there could still be a nail-biter in store, perhaps the closest since Colin Montgomerie beat Sam Torrance on the very last putt in 1995.
Of course, there will always be critics of season-ending jamborees and further evidence that they are not too high on the players' priority lists was provided by Tiger Woods withdrawing from the Tour Championship in Atlanta, joining Phil Mickelson on the sidelines. But there is no doubt they can provide excitement. When the pros can be as bothered as Casey, Howell and Harrington have been.