Shelbourne and Bohemians begin the first of two games inside the next week, with plenty riding on the League of Ireland Premier Division clash at Tolka Park.
Next week brings a FAI Cup date in Dalymount Park but this game has a huge bearing in the race to break into the top four.
It is one of two matches in hand on the teams currently in those positions, with Bohs able to overtake Dundalk if they avoid defeat.
Damien Duff's side can make it successive wins after their 4-0 success in UCD last week.
Matty Smith is closing in on a return to action but this game comes too soon. Tyreke Wilson returns after missing the game in Belfield.
Duff said: "In a Dublin derby, every fan may have their own favourite fixture, but I sense that this particular match is big for our fans. The players have been on it in almost every game against Bohs since I’ve come here, they have consistently stepped up over the past 18 months, even in games we lost at Dalyer, they showed fight.
"I expect more of the same tonight. We had a good performance against UCD, but listen, we know we’ll need to up that level again and play even better than we did last week.
"I sometimes think people can put too much stock on form, going into a Dublin derby, so much at stake, regardless of what happens, the last game, bad or good, doesn’t mean anything under the lights at 7:45pm.
"It’s an isolated game, a proper derby. Rivalry is there, a big match in the context of the league, a special one to be involved in, it means a lot to a lot of people."
Bohs announced the signing of Danny Grant last night - a major addition to their squad after his spell in England.
Declan Devine has hailed it as a major lift for the club: "I have been in constant contact with Danny for several months, have been over to see him in England, and I was always of the opinion that if he became available that I wanted to bring him back to the club.
"He has the DNA of the club running through him from his past stint here, which was a very successful period for him.
"He is at an age profile too where he really fits into this group. He has experience of playing in the league and of playing in England.
"I am delighted he wants to be part of the club again. He adds a dynamic and a quality to what we are trying to grow here."
Elsewhere, it's a big night for Drogheda United as they take on UCD at the Bowl.
With Sligo Rovers facing Cork City tomorrow, United can make ground into seventh place and open up a lead or bring Sligo further into the mire depending on the outcome of the game in the Showgrounds.
The 0-0 draw with Shamrock Rovers showed the best of United, competing well and creating chances against the leading side in the league.
United have one new signing after Kyle Robinson joined from Shelbourne yesterday.
The hosts will have many few faces but it's likely to be another difficult night after 11 defeats in their last 13 matches.
