Although Dolphins led only by a single point after the first quarter, increasing the advantage to 49-46 at the halftime break after Jermont Horton finished the second quarter with a lay-up.
Jekabpils stayed close throughout the third period. Although Edgars Jeromanovs and Adnan Chuck scored five quick points as the quarter was approaching its end to pull away by seven points, Troy Barnies and Rinalds Sirsnins replied with a 5-0 run of their own to cut the deficit to 71-69.
Another three-pointer by Sirsnins had made it a one-point game in the final period at 75-74, but a 6-0 stretch by the Dolphins put some distance between the sides again, as the hosts pulled away late to take the win.
Joakim Kjellbom and Kendrick Brown had 22 points each for the home side, while Pierre Hampton added 16 points and seven boards.
For Jekabpils, Rinalds Sirsnins finished with a game-high 20 points and seven rebounds, Troy Barnies collected 17 points, as Martins Kravcenko chipped in with 14.