Andrea Pavan produced a storming finish to win his first European Tour title after Padraig Harrington had looked destined to be crowned Czech Masters champion.
Harrington held a three-shot lead at the turn, having started in a share of the lead with Pavan at Albatross Golf Resort on Sunday.
The Italian was on a roll on the back nine, though, with five birdies sealing the title by two shots on 22 under - a tournament record - after signing for a five-under 67 in Prague.
Harrington had given himself breathing space by going out in 33 and made another birdie at the 13th, but the three-time major champion was level with Pavan on 20 under following his first bogey since Friday at the 15th.
Pavan, a winner of four Challenge Tour tournaments, holed a brilliant birdie putt from the edge of the green at 16 and the 29-year-old picked up another shot at the tricky penultimate hole to stand on the brink of his biggest win.
Europe Ryder Cup vice-captain Harrington could only finish his final round with three consecutive pars to card a three-under 69, missing out on a 16th European Tour win - and a first since October 2016 - five days before his 47th birthday.
Gavin Green took third spot with a closing 69 of his own, with Lee Slattery and Scott Jamieson a further shot back on 15 under.
Ryder Cup hopefuls Thomas Pieters and Eddie Pepperell finished with one-under rounds of 71 to take a share of ninth spot.