The Argentinian striker kept his composure after the ball had rebounded to him off Middlesbrough goalkeeper Jason Steele in the 91st minute to smash the ball home from 15 yards and clinch a 1-1 draw, extending Leeds' unbeaten run to 12 matches.
It was rough justice on the visitors, who looked to be heading for back-to-back victories after David Wheater's towering header had given them a first-half lead they rarely looked like surrendering.
Leeds announced the permanent signing of on-loan centre-half Andy O'Brien from Bolton before kick-off, but appeared to run out of steam against Tony Mowbray's well-organised outfit.
Source: PA
Source: PA