An extraordinary Casey made nine birdies in an eight under 64 at Panorámica Golf and Sport Resort in Castellón to move up one spot to second place on 19 under, two strokes behind American amateur Scott Fernandez.
With 18 spots in next weekend’s Final Stage on offer at each of the four venues, the rest of the Irish are outside the magic number.
West Waterford’s Gary Hurley hit a three 68 to move up 16 places to tied 21st on seven under at Lumine Golf and Beach Club in Tarragona and is just one shot outside the Top 18.
His close pal, Open Championship hero Paul Dunne, shot a level par 71 at the same venue, leaving him on two shots outside the mark on six under in joint 25th with Rathmore’s Alan Dunbar (70) tied 38th on four under.
The season is over for Moyola Park’s Chris Selfridge, however, after he tweaked his wrist on the range at El Saler when lying fifth overnight and was forced to withdraw before the start.
Walker Cup star Gavin Moynihan crashed to an eight over 80 at the Valencia venue and at five over par, he’ll need a round in the low 60s to progress to the Final Stage next weekend.
The two-time Irish Amateur Open champion from The Island dropped five shots in his first six holes and while he birdied the ninth, he double bogeyed the 15th and 16th and tied 53rd, eight shots outside the qualifying places.
A 69 for Derry’s Mick McGeady leaves him five shots outside the three under par qualifying mark at El Saler, where English Walker Cup player Jimmy Mullen leads on 12 under.
Europro Tour regular Casey opened with a 65 at Panorámica, followed up with a 68 and then took his birdie haul for the week to 23 with his 64 yesterday.
At Las Colinas Golf and Country Club in Alicante, Headfort’s Rory McNamara (73) is nine outside the qualifying mark on three over with Banbridge’s Richard Kilpatrick 10 over following an 80.
Meanwhile on the Asian Tour, Irish PGA champion Niall Kearney closed with a four under 68 to snatch a share of 20th in the Panasonic India Open in New Delhi.
Muskerry’s Niall Turner tied 41st on three over after a closing 70 and picked up $2,300 to lie 54th in the Order of Merit with $49,635 from five starts with Kearney earning €4,353.