Paul Rachubka, Leeds' 30-year-old American goalkeeper, was ignominiously substituted by an 18-year-old rookie, Alex Cairns, after a calamitous first-half display set Blackpool, his previous club, on their way to a crushing win.
Leeds, who had centre-back Tom Lees sent off when they trailed 1-0, were three down by the time manager Simon Grayson replaced Rachubka and four adrift when Jonjo Shelvey completed his hat-trick. The Liverpool loanee's 78th-minute goal, following two by Lomana LuaLua on his full debut, ensured the scoreline equalled the hosts' record home defeat, by Arsenal in 1980.
A "gobsmacked" Grayson, who defected from Bloomfield Road for Elland Road in 2008, described Rachubka's mistakes for the first three goals as "a kick in the teeth". Admitting he might bring in a keeper on loan before Sunday's visit to Leicester, he added: "Paul's really down and it's going to take a lot to pick him up. It was best for himself and the team that I took him off."
Ian Holloway, who released Rachubka to understudy Andy Lonergan at Leeds during the summer, said: "I like the fella. He did brilliantly for us and I hope things go better for him." The Blackpool manager, who echoed Grayson's doubts about the validity of Lees' dismissal when a point-blank shot hit his hand, preferred to concentrate on what was only his side's second away win this year. "That looked like my team," he said. "We played the way I wanted us to play."
In the 13th minute, after Ludovic Sylvestre's through-ball to Shelvey, Rachubka parried his shot straight to LuaLua, who scored easily. On 25 minutes, Rachubka spilled a routine catch from Alex Baptiste's cross and only Lees' illegal block kept out Sylvestre's shot. Referee Roger East reduced Leeds to 10 men before Shelvey scored with a twice-taken penalty. Shelvey almost walked in Blackpool's third in the 31st minute after another innocuous drive, by LuaLua, squirmed from Rachubka's grasp.
The sight of a distraught Rachubka lying face-down on the turf, and the booing that greeted his errors, prompted Grayson to send on Cairns for the second half. The debutant performed confidently in a much-improved showing but was helpless as first LuaLua cut in from the left to score with a brutal drive and then Shelvey rounded off what Grayson called "a freak night".
Leeds United (4-4-2): Rachubka (Cairns, h-t); Connolly, Lees, Kisnorbo, White; Snodgrass, Howson, Clayton (Vayrynen, 70), Pugh; McCormack, Keogh (Becchio, 46).
Blackpool (4-4-2): Gilks; Baptiste, Cathcart, Evatt, Crainey; Shelvey, Southern (Angel, 75), Ferguson, Sylvestre; LuaLua (Bogdanovic, 75), McManaman (Ince, 75).
Referee R East (Wiltshire).