In a game bereft of chances in the first twenty five minutes due to Jake Jessup wasting time with goal kicks, the only effort of note came in the 10th minute as a cross from the right was met by the head of Ben Thompson but the ball went narrowly over the bar.
Grays had to wait until the 34th minute for their first effort on goal as Leon Lalite played in Jack West on the left hand side of the area. With Joao Carlos well placed in the middle of the area for a simple tap in, Jack West instead fired low at goal which Jake Jessup saved with his foot.
The away side forced numerous corners in the first half but could not capitalise on any of them and went in at half time all square.
The second half started much the same as the first with Wroxham fragmenting play and wasting time as much as possible.
Grays almost took the lead in the 65th minute as Jack West turned his marker well on the right hand side of the area before finding Kenny Beaney. His left footed shot curled passed the diving Jake Jessup but also beat the far post.
Joe Sweeney, Joao Carlos and Jack West made way for Brian Moses, Kris Newby and Daniel Subuola throughout the second half as the game looked to be heading for a bore draw.
In the 90th minute Grays looked to have clinch a winner as Craig Pope and Kris Newby linked up down the right before Kris Newby's cross found Brian Moses at the back post. His header was clearly a yard over the line before Jake Jessup clawed the ball away but the assistant failed to keep up with play and no goal was given.
Just as victory looked to have been cruelly denied for the away side the breakthrough was made as Brian Moses flicked on a long pass into the path of Daniel Subuola who raced through on goal and fired passed the advancing Jake Jessup to give Grays a vital win.
Grays now top the league by 3 points from Maldon & Tiptree still with 1 game in hand after notching up 11 league victories in a row.
Grays Athletic: Lamar Johnson, Craig Pope, Junior Baker, Ryan Kirby, Lee Flynn, Danny Bunce, Kenny Beaney, Leon Lalite, Joao Carlos (Kris Newby 73), Joe Sweeney (Brian Moses 59), Jack West (Daniel Subuola 87)
Unused Subs: George Kamurasi, David East