Seimone Augustus poured in a game-high 22 points for Dynamo Moscow but it wasn't enough to hand Ros Casares their first defeat of the campaign with the Valencia club holding on for a 55-53 victory.
Ros improved to 8-0 in Group D of the EuroLeague Women, with UMMC Ekaterinburg and CSKA Moscow the only other teams with perfect records in the competition.
Spanish giants Ros got a major scare from Dynamo, who took a 33-30 lead at the start of the second half on a jump shot by Augustus, a basket that took her points haul to 12.
Spain international Laia Palau replied for Ros with a three-ball, though, and a Katy Douglas lay-up shortly after made it 35-33.
Ros Casares led the rest of the way, although Dynamo chased them hard until the end.
An Augustus jumper with 30 seconds remaining closed the gap to 55-52.
Palau missed for Ros, and with five seconds left she fouled Anete Jekabsone-Zogota, who made the first free throw to cut the deficit to two.
Jekabsone-Zogota, the leading player in Latvia's national team, missed the second attempt, and Augustus grabbed the offensive rebound.
But Augustus, the star of the game, put up a jump shot that was off target before former Ros Casares player Tangela Smith, who just signed for Dynamo, tried unsuccessfully to tap the ball in.
Smith finished with 10 points and 11 rebounds against her former team while Jekabsone-Zogota also scored 10, pulled down five boards and dished out four assists.
For Ros, the American duo of Delisha Milton-Jones and Douglas each scored 15 points. Milton-Jones also had 14 rebounds although she turned the ball over seven times.
Ros might have had a more comfortable win had they made their free throws.
They finished nine of 17 (56.2%), compared to eight of 10 (80%) for the team from Russia.
Manolo Real, coach Ciudad Ros Casares:
"We should have won the game early on, but we lacked a cool head and tranquility. Our outside players were not weak and we managed to keep into the game, but ultimately it was the defense which gave us victory".
Ainars Zvirgzdins, coach Dynamo Moscow:
"I am disappointed because we lost. We wanted to win in Valencia, but we can't play with Nuria Martínez because she is injured. The defense of Ros Casares was very good and our offense can testify to it".