Manchester United had to settle for a 2-2 draw after seeming on course for victory for most of their friendly against Aston Villa in Perth on Saturday after Calum Chambers scored the equaliser with the last play of the match.
Chambers headed home from a Leon Bailey corner just before the whistle, ending United's perfect pre-season record.
When Jadon Sancho opened the scoring for United at the Opta Stadium and Matty Cash sent one into his own net, United were comfortably ahead 2-0.
But after the break, Villa came into their own. Bailey pulled one back with a superb solo goal shortly after his half-time introduction and Chambers headed home his corner with the last touch of the night as David de Gea was caught in no-man's land.
There was earlier uncertainty over the fate of the match. The pitch at the Optus Stadium had become waterlogged following overnight showers and early morning thunderstorms.
Ground staff worked hard to remove surface water and following a pitch inspection, the match referee declared the pitch to be playable.
However, danger persisted as both sides managed to avoid serious injury on the poor surface in Perth, where a crowd of 58,228 saw Steven Gerrard's Villa overturn a two-goal deficit.
The last-gasp Chambers header denied manager Erik ten Hag a winning end to their pre-season tour of Thailand and Australia.
There was some positive news for United. Captain Harry Maguire did not face any noticeable negativity days after being booed in Melbourne.
He was in the action early with a superb header that was brilliantly saved by goalkeeper Emiliano Martinez.
The Argentine was helpless in the 24th minute when 22-year-old Sancho powerfully struck home the volley after Luke Shaw and Marcus Rashford combined well on the left side.
Amid torrential rain just before half-time, Sancho continued to menace with a wicked cross smacking into Villa's Cash for an own goal.
Ten Hag resisted making changes at half-time, but Gerrard's decision to bring on winger Bailey proved inspired with the Jamaican nailing a long-range shot to claw Villa back into the contest.
The speedy Bailey threatened an equaliser against a new-look United, after Ten Hag rang the changes in the 68th minute, but it was Chambers who stepped up at the death.
United had notched convincing win over Liverpool, Melbourne Victory and Crystal Palace ahead of their Premier League opener against Brighton on August 7.