TonyBet got off to a superb start, taking a 17-2 lead after an and-one play by Zygimantas Janavicius midway through the first quarter.
Although the Lithuanians were still up by double digits with five minutes remaining in the first half, Rock did not panic and finished the quarter strong, to cut the deficit to 41-42 at the half.
The visitors continued to ride the momentum in the third quarter and even led by as many as eight points after a basket by Vincent Simpson.
The game took a swing in a different direction again in the final period, as the experienced TonyBet team went on an early 8-0 to retake the reigns of the game with solid play.
With 90 seconds remaining, it was still a five-point game, but Gintaras Kadziulis hit a very difficult off-balance three-pointer to shoot down Rock’s hopes of a comeback.
Arturas Valeika had a game-high 22 points for the Prienai side, Gintaras Kadziulis scored 18 while Martynas Linkevicius finished the game with 11 points, 12 rebounds, five rebounds and three steals.
For Rock, Joosep Toome had 19 points, Janar Talts collected 16, while Gert Dorbek rounded out the double-digit club with 13 points and six assists.