Italy sprung out a major surprise by edging Russia 47-46 in Group F.
The Azzurrine led 46-44 with 23 seconds remaining and had the ball when Oriana Milazzo turned it over and gave Russia a chance to pull level or take the lead with a three-pointer.
Russia's Alexandra Stolyar knotted the contest with a basket and was fouled on the play, but missed the free-throw and Italy's Federica Tognalini rebounded.
With eights seconds on the clock, Stolyar then fouled Milazzo, who went to the line and made the first but missed the second.
The Russians failed to box out Tognalini, however, and she got the offensive rebound to preserve victory for Italy - their first win in the Qualifying Round.
"Luckily the ball just fell into my arms," a delighted Tognalini said.
"I held onto it with all my strength.
"This win means everything to us. After yesterday's defeat to France, we knew we needed to win this game to change our fortunes in the tournament.
"We fought for 40 minutes and we deserved this win."
The defeat was a blow for Russia, who had hoped to bounce back from their 77-64 loss to Lithuania 24 hours earlier.
Russia led 42-36 going into the final quarter but committed nine of their 33 tunorvers in the last frame.
Alessandra Tava led Italy with 11 points while Russia's Viktoria Medvedeva had a game-high 15 points.
However, she turned the ball over six times.
Anastasia Pasynkova made Russia's only attempt from behind the arc (one of 19) while the Italians finished three of 15 from long range.
Russia outrebounded Italy 44-30.