fall at the last hurdle

Probably from hurdling, a type of horse racing where horses jump over obstacles called hurdles. The term refers to a horse successfully clearing all but the last hurdle.

• "[W]hen she [Psyche] falls at her last hurdle, it is through her own act, motivated by the identical combination of curiositas and simplicitas that has been her undoing from the start."
• "Now, at the point of action, it's easy to appear to fall at the last hurdle. In fact, you are unlikely to fail here. If it goes wrong now, it will [be] because you slipped at a previous waterjump and didn't notice the splash you made."
• "Mortal Kombat 2 is the sequel to Mortal Kombat. […] Sub Zero—the mysterious icy ninja, is one of the best fighters out of the brave warriors trying to save earth from the hands of Shao Khan. Falling himself also at the last hurdle of doing away with Tsung, wants to get his frosty hands on Khan now."
• "[T]he resources of local land settlement commissions could be tied up for many months or years in a continuous process of devising and revising enclosure projects, only for the final project to fall at the last hurdle."
• "Armagh (and it is one of the most memorable chapters in the history of Gaelic football) were fated to fall at the last hurdle when they were beaten by Kerry in the All-Ireland decider."
• "I remembered my failed attempt at flying training, how I had fallen at the last hurdle."
• "Some units penetrated as far as the last street before the river, but once more poor intelligence, lack of coordination and limited firepower meant that Operation Iron Fist fell at the last hurdle."

• fall at the final hurdle
• fall at the last

• cross the line
• go all the way