McIlroy (left) and McDowell led the way for Britain and Ireland
Great Britain and Ireland took a commanding 12½-5½ lead over Continental Europe in the Vivendi Trophy with just Sunday's 10 singles matches to come.
The holders now only need two points for a fifth-successive victory.
Rory McIlroy and Graeme McDowell led off the greensomes and foursomes and won both to take their personal tallies to three points out of four.
They beat Swedes Henrik Stenson and Peter Hanson 2&1 and Danes Soren Hansen and Soren Kjeldsen by the same margin.
"We really fed off each other, it was a great day's work and we couldn't be happier," said McIlroy.
The 20-year-old from Northern Ireland was also full of praise for captain Paul McGinley.
"We've got a great captain. He's been fantastic and has never left us in the dark. He's got a lot of good ideas about team golf and has put some of that into practice, so I think a lot of the credit has to go to him," he added.
Europe's Stenson is the top-ranked player on either side at world number five and he looked like suffering a fourth successive defeat in his second game on Saturday.
Playing with Hanson again, they won the last three holes to halve with Nick Dougherty and Steve Webster, with Stenson sinking a 25-footer on the last.
By then Chris Wood had already made it four wins out of four in the game behind.
After twice being successful with Anthony Wall he linked up with Ross Fisher and they recorded a double over Anders Hansen and Francesco Molinari.
Simon Dyson and Oliver Wilson lost their 100% record just before lunch when they bogeyed the last to lose to Alvaro Quiros and Miguel Angel Jimenez.
The Spanish pair were kept together for the foursomes, but Continental Europe were left needing a miracle when they lost on the last to Wilson and Robert Rock, who had been drafted in to replace Simon Dyson after he continued to struggle from the after-effects of food poisoning.
Scores from Saturday's greensomes (GB & Ire team first):
McDowell & McIlroy bt Stenson & Hanson 2&1
Rock & Dougherty bt Karlsson & Fernandez-Castano 5&4
Fisher & Wood bt Hansen & Molinari 1 hole
Dyson & Wilson lost to Jimenez & Quiros 1 hole
McDowell & McIlroy bt Hansen Kjeldsen 2&1
Dougherty & Webster halved with Stenson & Hanson
Fisher & Wood btHansen & Molinari 3&2
Rock & Wilson bt Quiros & Jimenez 1 hole
Sunday's singles (BST)
McIlroy v Stenson (1016)
McDowell v Karlsson (1028)
Wall v Quiros (1040)
Fisher v Jimenez (1052)
Webster v Soren Hansen (1104)
Dyson v Kjeldsen (1116)
Rock v Fernandez-Castano (1128)
Dougherty v Anders Hansen (1140)
Wood v Hanson (1152)
Wilson v Molinari (1204)