Ekat met early resistance from the Polish outfit and trailed 33-32 midway through the second quarter.
Agnieszka Bibrzycka then shifted the momentum to UMMC with a three-ball.
The shot ignite a 14-0 run that put UMMC in front to stay.
Having led 48-35 at the break, UMMC emerged from the changing rooms with a full head of steam.
Two minutes into the second half Sandrine Gruda scored to take her points haul to 18 and give UMMC a 56-36 advantage.
Gdynia clawed their way back and pulled to within 65-55 late in the third quarter when Monica Wright sank a pair of free-throws.
Cappie Pondexter, however, had an answer.
She triggered an 8-0 surge with a tip-in as UMMC took command for good.
UMMC improved to 6-1 with the win and pulled to within a point of Fenerbahce, who thrashed Gospic Croatia (0-7) on Wednesday.
Bibrzycka and Gruda each had 20 points and Crystal Langhorne 18 for UMMC.
Center Milka Bjelica had 17 points and seven rebounds for Lotos.