Six goals from Matt Smith and three from Noel Hunt inspired a 16-0 win as United’s amateur opponents capitulated in Santa Cristina.
The victory was United’s biggest ever in a pre-season fixture, eclipsing a 15-0 rout of Swedish club Byske back in 1999.
Hunt helped blow Gherdeina away with a first-half hat-trick as Leeds amassed a 7-0 lead at the break and continued to run riot in the second period.
The Republic of Ireland international set the result in motion with two early headers in quick succession and sealed his hat-trick with a penalty before the half-hour.
Two efforts from striker Steve Morison and one apiece from Lewis Walters and David Norris - the latter’s a fine volleyed effort - pushed the scoreline close to double figures by the time the interval arrived.
New head coach David Hockaday - in charge for the first time since his appointment last month - fielded different line-ups in each half, with goalkeepers new signings Marco Silvestri and Stuart Taylor both involved.
Trialist Andre Blackman featured as a second-half substitute but midfielder Tommaso Bianchi was absent with Leeds waiting for his transfer from Sassuolo to be officially registered.
Smith, who is wanted by Championship club Millwall, weighed in with two headed goals shortly after the restart and completed a hat-trick of his own minutes later.
Luke Murphy added goal number 11 from long range and Smith snatched his fourth before Dominic Poleon increased Gherdeina’s torment.
Smith and Poleon were on target again in the closing stages and Smith’s sixth strike of a serious mis-match completed an easy rout.
The club’s next friendly takes place against Romanian side Viitorul Constanta in Santa Cristina on Sunday.
Leeds 1st half: Silvestri, Byram, Killock, Pearce, Taylor, Austin, Norris, White, Hunt, Morison, Walters.
Leeds 2nd half: Taylor (Cairns), Thompson, Lees, Skelton, Warnock, Cook, Tonge, Murphy, Dawson (Blackman), Smith, Poleon.