Trevor Gordon, with 28 points, and Joe Hillman, with 25, had the power and control to capitalise on the absence of Worthing's 6ft 9in American Herman Harried.
The variety of Manchester's offence was highlighted by their own 6ft 9in pair of Gordon and the American Chris Fite. When Worthing expected them to take the ball inside, they were as likely to stay outside the three-point arc and shoot.
Fite hit three 'threes' and Gordon scored two in the first period, which Giants brought to a storming close by upping the tempo to return to the locker room 59-47 ahead.
Giants' Hillman, a product of Bobby Knight's University of Indiana, enjoyed a freedom in the back court which Worthing's Cleave Lewis rarely found. Colin Irish and Mike Spaid shot their share of three-pointers to keep Worthing in touch, but a critical factor of the second half was that Spaid failed to add to his first-period total of 15.
Lewis hauled Worthing back to trail 79-75, scoring six second-half free throws, but then Gordon and Hillman reapplied the pressure.
Riga beat holders Thames Valley Tigers 92-89, following a three-point play nine seconds from time by Rauno Pehka, one of their nine internationals.
Leading scorers: Manchester: Gordon 28, Hillman 25. Worthing: Irish 28, Lewis 20; Thames Valley: Lloyd 30. Riga: Zeidaks 20.Reuse content