MARC Harrison insists Tilbury’s performance levels must improve if they are to enjoy a successful season.

The Dockers are set to go head-to-head with Aveley in an exciting local derby at Chadfields on Saturday.

And Tilbury will be looking to bounce back from their FA Cup exit following a 2-1 first qualifying round defeat to Biggleswade.

Harrison said: “I feel we let ourselves down.

“We got a man sent off, which put us in a difficult situation, but then went 1-0 up going into half-time.

“But we then lost 2-1 and, judging the performance over the course of the 90 minutes, it was not what I was looking for.

“I feel as though it was a missed opportunity and I was disappointed not to be in the hat for the second qualifying round.

“The performance levels have to be better.

“The Isthmian North is a very strong division this season and we are hoping to get back to winning ways against Aveley.

“There is a great rivalry between the two clubs and we are looking forward to the game.

“But we know that we have to improve if we want to achieve anything this season.

“I want us to progress as a club and, for me, that means promotion.

“That is what I’m striving for but things have to get better.”

The Dockers will be without Jordan Cox for this weekend’s derby after the striker saw red in the defeat at Biggleswade.

Having already missed a golden opportunity to put Tilbury in front, Cox was dismissed for a high challenge soon after the half hour mark.

Despite the setback, Harrison’s side broke the deadlock six minutes later as Tommy Barton sent an unstoppable volley into the back of the net.

George Sykes was kept at bay as Tilbury went in search of a two-goal cushion.

And Tyler Josephs’ save proved crucial as Biggleswade levelled matters 10 minutes after the interval.

Alex Marsh confidently despatched a penalty after a foul by goalkeeper Connor Wheatley.

It looked as though the sides would be heading for a replay, but Tilbury suffered a cruel blow two minutes into stoppage time as Ryan Inskip crashed home the winner from the edge of the penalty area.