Colin Montgomerie strengthened his bid for a remarkable eighth Order of Merit title as he moved into a two-shot lead in the Volvo Masters at Valderrama.
GB&Ire unless stated
-9 C Montgomerie
-7 S Garcia (Sp), I Poulter
-4 B Dredge
-3 N O'Hern (Aus), H Stenson (Swe)
-1 M Campbell (NZ)
Montgomerie produced some inspired golf in his round of 66 to reach nine-under, but a final-hole bogey spoilt his card.
Sergio Garcia and Ian Poulter tied for second at seven under, with Bradley Dredge a further shot back in third.
Michael Campbell, the only player who can deny Montgomerie the Merit title, ended at one under for a share of 11th.
The 42-year-old Scot, who last won the Merit title in 1999, made seven birdies including three from the first four holes.
"I'm delighted to be in this position," said Montgomerie.
"I'd have bitten your hands off before the tournament started if you'd offered me this position at halfway.
"I came here with all sorts of pressure and anxieties and all sorts of stuff going on, so I am proud of that. That was very, very good."
Montgomerie suffered a minor mishap at the 10th as he dropped a shot, but birdies at the 11th, 13th and 14th pulled him clear of the chasing pack again.
A brilliant 30-foot putt at the 15th saved his par after he went into a bunker but his superb round was marred by a careless miss at the last for his second bogey.
Montgomerie, though, said the fading light was partly to blame and will not be pleased that he has the same tee-off time of 1420 local time for the third round on Saturday.
Earlier he said: "It's very dark here and hopefully we'll start a little bit earlier.
"There's no need to be starting (as late as) 0950. It gets so dark and it's difficult to read the lines of the putts.
"I'm not blaming that, but it is a little bit unfair for the later starters to have that added problem.
"Sometimes we have to think about the players."
Campbell was unlucky to be so far behind Montgomerie after his two-under round of 69.
But the Kiwi admitted his hopes of pipping Montgomerie to the Merit title were relying on the Ryder Cup hero losing the plot in spectacular fashion.
"I've got another two rounds to go. Monty is up there doing his stuff once again, but I can't really control what he does," he said.
"I can only control my own destiny here, and I'm just going to play the same way I've been playing for the next two rounds."
Partnering Montgomerie on Saturday will be Spaniard Garcia, who fired a second-round 67 to put himself in contention.
"I haven't done anything extraordinary yet," said the world number six. "If I keep playing the way I've been playing I should have a chance.
"That's the main goal - give myself a chance and put some pressure on Monty and see how we can both handle it."
Northern Ireland's Darren Clarke was forced to withdraw from the event because of his wife's ill health.