The last four meetings between the sides have been dramatic, with last-minute wins for Coastal in May this year and May 2024, while United upset their opponents in August last year to claim the Hurley Shield – which they held until Coastal won it back off them this year.
All of those were in the Southern League. The sides will meet for the first time at national level at Linfield Park at noon on Saturday.
“It's become a pseudo-local derby over the last 12 months,” said United captain Jago Godden.
“They've got us over a few times. The real goal throughout the National League is to finish somewhere ahead of them and up in the top spots. If we want to do that, we need to beat teams like Coastal.”
The teams come in contrasting form, United slipping up in their last two games, including a competitive 2-1 loss to Northern League champions Western Springs at home on Saturday.
United had won their opening two games, and sit fifth on the ladder.
Coastal endured a poor start but got on the board with a 1-0 win over Auckland FC Reserves on Saturday, new signing Derek Tieku scoring the winner which lifted his side off the bottom, up to 10th.
Both teams are still in the running to finish in the top two and make the final with seven rounds remaining, United one point off second-place Western Springs and Coastal four adrift.
