New boys Denny Johnstone (pictured) and Navid Nasseri were on the scoresheet for Alan Thompson's side; with former Celtic man Johnstone scoring a brace.
On a blustery afternoon at Wast Hills, Blues gained the advantage after just six minutes. Viv Solomon-Otabor beat his marker before finding Nasseri who laid it into Johnstone's path for the Scot to sweep the ball home.
But the lead lasted only a minute as the hosts were caught out on the break and Hull levelled the scores.
Blues began to put together some neat passages of play and were zipping the ball around well, but they found themselves behind just before the half-hour mark when they failed to deal with a free-kick and the ball was eventually headed home by the Tigers.
Johnstone then tried his luck from distance on two occasions, but his efforts were just off target.
With half-time approaching young Blues keeper Connal Trueman produced a fine save to tip a goal-bound effort behind for a corner and keep Blues in the match.
With just over an hour on the clock, Blues were right back in it when George McGee's slick pass found Nasseri and the Iran U21 international showed good composure before firing the ball past the advancing Hull keeper.
With Hull still regrouping, Blues sealed the victory just 30 seconds later after Johnsone robbed the centre-half and side-footed the ball home to make it 3-2.
Hull looked to find an equaliser, but were prevented from doing so after Will Packwood put in two excellent blocks and Trueman fashioned another fine diving save with just minutes to go.
Trueman, Dacres-Cogley, Hancox, Adams (Webb, 55), Kelly, Packwood, Solomon-Otabor, Lee, Armstrong (t) (McGee, 63), Denny Johnstone, Nasseri (Moseley, 85).