It's the game Harps fans have been waiting for ever since the fixtures for the new season were confirmed back in December.
Their team's first game back in the Premier Division since 2008 was always going to be a big one.
The fact that it's against their bitter north west rivals adds more than a little spice to the occasion.
Harps only got clearance for a number of their new signings on Wednesday, which will hardly help the club's preparations for the big game.
But Ollie Horgan will still hope to be ready and competitive when the season kicks-off on Friday night and the Harps team should include a number of the new faces who have signed.
Among them will be Sean Houston, a player back for his second spell at Harps having done well at both Bray Wanderers and Derry City in the top division.
Another former Derry player, Ryan Curran, is also expected to be involved while Adam Hanlon, Liam Flatley and Dave Scully could also feature.
The team will of course, also include several of the players who were involved in the dramatic play-off wins over UCD and Limerick which saw Harps promoted back to the top tier.
Horgan will need another big performance from his players as he plots a win in the opening game which would be the perfect start to the season.
“It's not going to be easy,” Horgan warned this week.
“We're up against a full-time team and that's the way it's going to be this season. We're going to be up against a lot of full-time sides who are better equipped than we are.
“Derry City on paper, are a better side than we are. They have a number of players who bring quality and experience to their team.
“So we know the task that's facing us and we'll need to be up for the challenge.”
Horgan again made reference to his team's pre-season campaign and suggested that the team didn't perform too well in some of their friendlies.
“We haven't been going particularly well,” he said, although Harps did finish off their pre-season campaign with a 1-0 win over Drogheda United in Dublin last Saturday.
Tickets are selling fast ahead of Friday night's game but one player who won't be on show is Barry Molloy.
The former Derry City man signed for Harps last week and linked up with the club for the first time at training last Thursday night.
The midfielder announced his retirement from the game in January with reports suggesting that he turned down an offer to re-sign for Derry.
In stepped Ollie Horgan and Molloy's arrival could well be his best piece of business this season.
The 32 year old is not considered match fit and he won't be included in the squad on Friday night.
Like Horgan, Derry's new manager, Kenny Shiels, will be taking charge of his first ever SSE Airtricity Premier Division game tomorrow night.
Derry struggled for much of last season before they eventually pulled clear of the drop zone in the closing period.
The City faithful will not be happy if their team doesn't get off to a winning start against their neighbours.