Brier and Wiegele could not get up and down for par from a greenside bunker at the 18th at Real Club de Golf Sevilla. That bogey gave them a 2-under 70 and a two-round total of 14-under-par 130.
The English team was one back in third place after Thursday's opening round, but wasted little time in getting the top spot on the leaderboard. The pair birdied four in a row from the third to go two clear of the field.
Donald and Casey, both of whom represented Europe in this year's Ryder Cup, did not relent. Casey drained a 20-foot birdie putt at the eighth to go three ahead, then Donald knocked the team's third to 10 feet to set up another Casey birdie putt at the par-5 ninth.
The duo kept their huge margin even when they ran into trouble. At the 10th, Casey drove into the right rough, and Donald hit the approach well left of the green. Casey pitched to 20 feet and Donald sank the par putt to keep their large lead.
Donald's second at the par-4 12th spun back to 3 feet. Casey tapped in the birdie putt, then holed a 5-footer for birdie at 14 after Donald blasted out from a greenside bunker. The English team made it three in a row at 15 when Donald's approach from a fairway trap came up 18 feet short. Casey converted the birdie try to give England a six-shot advantage.
The Austrian team clawed back with a 6-foot birdie putt at the 13th. They trailed by five and looked like they might gain another stroke when England appeared to be in danger at the par-5 16th.
Casey drove in the water right and after a drop, Donald hit a fairway-metal from the rough that just cleared a lake guarding the green. Casey chipped 5 feet short of the flag, but Donald drained the par-saving putt.
At the 18th, Donald's second landed over the flag in the back rough. Casey chipped 8 feet past the hole and Donald played too much break in his putt. The team made bogey and saw its lead slip to four.
But Austria, who played in the final group on Friday thanks to sharing the first-round lead with Ireland, also had problems at 18. The team was over the green in two and also failed to save par, giving England a five-shot lead with two rounds to play.
'I think we played very solidly today,' said Donald. 'I think our plan was to give me a lot of iron shots and leave Paul with all of the putts. He's putting great right now. That kept our momentum going.'
So England has a five-shot lead, but does that mean they will play conservatively on Saturday?
'The beauty is we've got four-ball tomorrow,' said Casey. 'There's no reason to hold back with two balls in play tomorrow. We'll try to put together something in double-digits, 10-under or plus. Hopefully we'll be in a good position for Sunday.'
The Austrian team was a shocking co-leader after the opening round considering they were not even qualified for the tournament. They missed the mark by three strokes in a qualifying event last month in Mexico, but when Thailand withdrew, the Austrian side got a spot.
Austria started poorly with a bogey at the third, but rebounded with a birdie at the eighth. They combined for three birdies in a four-hole span from the 10th to get into a share of second with Ireland, but Padraig Harrington and Paul McGinley fell on hard times on the back nine.
Harrington and McGinley, who won this event in 1997, was in second throughout much of the second round, but disaster struck at the par-5 16th. McGinley needed to roll in a 35-footer for bogey, but came up almost 4 feet short. Harrington made the putt for double bogey and parred out for a 1-under 71.
The Irish team is tied for third place at 13-under-par 131 with the defending champion South Africa (Rory Sabbatini & Trevor Immelman, 65), Sweden (Fredrik Jacobson & Joakim Haeggman, 67), the United States of America (Bob Tway & Scott Verplank, 67), Japan (Shigeki Maruyama & Hidemichi Tanaka, 69) and host country Spain (Miguel Angel Jimenez & Sergio Garcia, 68).
Australia's team of Nick O'Hern and Stephen Leaney posted a 4-under 68 and are alone in ninth place at 12-under-par 132. Marcel Siem and Kariem Baraka of Germany carded a 3-under 69 and are in 10th at minus-11.