That is exactly what happened this afternoon when play was abandoned at the third Test in rainy Manchester, leaving the match in a draw and England with a 2-0 lead in the series with two Tests left to play.
"It's been a strange day for the lads but we've retained it after three games, played good cricket in the first two, fought hard and had a little bit of a luck today with the weather. It's nice to retain the Ashes," he told Sky Sports News.
"It's been a really good series. We played well at Lords, Trent Bridge was a nail-biting game and in this game it was an important toss to win but Australia played well, put us under pressure getting 500 but we responded well with the wicket getting harder. We fought hard."
Victory in the fourth Test in Durham will guarantee a series victory for the hosts.
"If you'd said [we would have retained] after three Tests, I'd have snapped your hand off to be in this position," added Cook. "It's a nice feeling, we'll enjoy it tonight but we'll go to Durham and work hard there."
Cook's opposite number Michael Clarke was awarded man of the match for his 187 runs in the first innings.