Australia batsman Usman Khawaja was left to rue a "frustrating" ball change which he believed played a key role in England's fightback to win the fifth Ashes test at The Oval.
The tourists started Monday's last day on 135-0, needing just 249 more runs to reach an imposing victory target of 384.
But England's Chris Woakes struck twice early on, taking two wickets in seven balls as he removed both David Warner (60) and Khawaja (72) following their impressive opening stand.
The ball appeared to be moving significantly more in the air and off the pitch than it had on the fourth day.
And while overhead conditions and a rain-freshened pitch may have played their part in making batting conditions more difficult, a change of ball, brought about when England fast bowler Mark Wood hit Khawaja on the helmet late on Sunday, may have been a factor as well.
In these circumstances, the on-field umpires are supposed to select a replacement ball in similar condition to the one being discarded.
But television pictures suggested the replacement ball was significantly newer than the old ball and that there did not appear to be one of equal wear and tear for the umpires to select from a box of replacement balls.
'I DONT KNOW WHAT'S GOING ON'
"I walked straight up to Kumar (Dharmasena, the umpire) and said straightaway, 'That ball looks nothing like the one we were playing with. I can see writing on it'," Khawaja told cricket.com.au after Australia had been bowled out for 334 to give England a 49-run victory.
"It felt harder than any ball I've faced in this Ashes series –- and I've opened the batting against the new ball every single time," added Khawaja, the leading run-scorer on either side in the five-test campaign with 496.
"I said, 'I don't know what's going on –- you've gone from an old, reverse (swinging) ball to a brand-new ball.
"Personally, I think if there's nothing else in the box that can match the ball you have, you can't really change it.
"It's a bit frustrating as a batting unit because we worked our backsides off for 36 overs and then they changed the ball.
"As an opener you work so hard to get through to there and then you're facing a new ball again."
Khawaja added he hoped the International Cricket Council would take note of what had happened, adding: "Unfortunately, that's the hand you get dealt sometimes in cricket.
"It may not feel fair, but hopefully the ICC can learn from it and try to look at that ball to change the process."
The drawn series meant Australia, as the holders, retained the Ashes.
But a shared campaign left Australia still waiting for a first Ashes series win in England in 22 years.
Former Australia captain Ricky Ponting was in no doubt the ball change had played a decisive role at The Oval.
"There is no way in the world you can even look at those two balls there and say in any way they are comparable," Ponting told Sky Sports.
"That is a huge moment in this game. And something I think has to be investigated."