Batting first, Whitby began slowly, but were starting to accelerate when Andrew Marshall was dubiously given out lbw.
Despite an early-season struggle with timing, opener "Spike" Fawcett kept the score moving throughout, taking quick singles and pushing for twos and threes.
No-one could stay with him though, and his 22 was the only score above double figures in Whitby's disappointing 20-over tally of 79/8.
Hinderwell's young opening bowlers, Steyart and Garbutt, trooped out after the interval to open the batting.
They played steadily at first, but first Steyart and then Garbutt set their sights on the short western boundary.
There was little Whitby's bowlers could do in reply.
Steyart was eventually caught off the bowling of Adam Hogarth, but the damage had been done.
Garbutt smashed 10 runs in three balls to win the match in the 17th over.