The game nearly got off to a perfect start when Alex Flett found space inside the box as leading scorer Marc Cooper found Jonathan Oglesby on the wing but Flett’s shot was blocked.
The visitor’s then came close in the fourth minute when Mike Tambling tried to audaciously chip Owls keeper Miles Fenty but he was more than a match for it.
As the game settled both sides struggling for last third penetration. Westfield’s Sam Gwynne tried to test Fenty from distance but it was easily saved. Then Fenty managed to sprint out ahead of Captain Jamie Cuss.
Westfields pushed further forward and should have scored through Tambling but he had strayed into an offside position from a Cuss cross with the goal at his mercy.
Frustration for the hosts continued as Cooper, Flett and then Darren Hanslip all found a Westfield’s defender blocking each and everyone of their shots.
Winger Luke Mascall came closest for the Owls when he tried to back heel a Trott shot goal bound but Matt Gwynne was on hand to pounce on the loose ball.
The half ended with Westfield coming the closest as Craig Jones rattled the bar from a 35 yard lobbed effort with Fenty stranded as an onlooker.
The second half started at a slow pace, however in the 49th minute Cooper had a golden chance to score but as he sprinted clear and rounded the keeper he fluffed his shot and it dribbled back into the keepers arms.
Almost immediately Westfields went up the other end and scored. The ball was not cleared effectively and it fell to Glover who sided footed home.
Trott then, in the 55th minute had a great chance to equalise but his header was was saved then the renounced was struck against the side netting from 3 yards out.
Just after the hour mark, Mascall controlled a long ball brilliantly from the right but with the keeper only to beat his shot was straight at Gwynne who has rushed out to narrow the angle.
Six minutes later though and the Owls were level. A great move from involving Peter Winn and Flett who played a lovely weight through ball to Trott who powered home a low shot.
It was nearly two in a minute as Trott was denied, then substitute Brody Robertson’s shot fell to Mascall who side footed wide.
Robertson came even closer two minutes later when he rounded the keeper and looked almost certain to score but his shot came back off the bar and bounced the wrong side of the line.
With the Owls in the ascendancy they went in search of a winner and managed to get it from the penalty spot. Mascall was upended inside the penalty area and Cooper it was who slotted the ball coolly home to put the Owls in the hat for the next round.