(All games Saturday 2.30 unless stated)
DIVISION 1A
Clontarf v Shannon, Castle Avenue
There were four 'Tarf players in the Ireland Clubs international side that defeated English Counties. The club has paid the price, wing Tim McCoy dislocating his shoulder.
Cork Constitution v St Mary's College, Temple Hill
St Mary's coaches Hugh Hogan and James Norton know the champions are not yet out of trouble. They need win number five at one of the most testing venues in the league.
Lansdowne v Garryowen, Aviva Stadium
Coach Mike Ruddock has seen his players carve out a seven-point lead at the top of the table, underpinned by the control of fly-half Craig Ronaldson.
UL Bohemian v Old Belvedere, Annacotty
Coach Andy Dunne will know the value of four points here to put distance between the Black & Whites, in seventh, and the second-from-last Limerick club.
DIVISION 1B
Ballymena v Dublin University, Eaton Park
The gap between Trinity in second and UCD in third is down to two points. Flanker Dominic Gallagher returns after injury.
Ballynahinch v UCD, Ballymacarn Park
This must be the last place College would have wanted to go given 'Hinch's unbeaten record. Jordan Coghlan will start at centre and Jamie Glynn at scrum-half.
Blackrock College v Belfast Harlequins, Stradbrook
Coach Ben Manion will stress as 'Rock conceded 36 points to Buccaneers, but still salvaged a draw in Athlone to make it unbeaten in their last three.
DIVISION 2A
Cashel v DLSP, Spafield
Full-back Michael Nevin and second row Victor Ball are expected to pass fitness tests, while Phil de Barra broke his leg on his first involvement last week.
Corinthians v Terenure College, Corinthian Park
'Nure are sitting very pretty on top of the division with a game to spare on UCC. But they will have their work cut out at Corinthians.
Midleton v Greystones, Towns Park
Coach Reggie Corrigan will have to make a decision between Alan Dempsey, returning from injury, and Conor Savage at openside.
Old Crescent v Bective Rangers, Rosbrien
Rangers coach Kevin Lewis will hammer home the significance of each and every point for a club six points above bottom club Salmo'.
Old Wesley v Queen's University, Donnybrook
Wesley are coming off the back of a morale-sapping defeat to fellow Donnybrook tenants Bective three weeks ago. They need this one.
Seapoint v Highfield, Kilbogget Park
Coach Declan Keegan will go with the same team that led Cashel until a two-try blitz last week.
DIVISION 2B
Skerries v Navan, Holmpatrick, Friday 7.30
The home side are starting to motor, winning their last three to move up to eighth. The Meath club will look to build on their form from a friendly against Wanderers last week, prop Eoin King leading the charge with two tries.
Armagh v NUIM Barnhall, Palace Grounds
Wing Matthew Mellotte, hooker Dewi Harrison, lock Rob Tiernan and flanker Sam Condon are the quartet of changes made by Dennis Bowes.
Instonians v Boyne, Shaws Bridge
Player/coach Craig McGrath has Boyne positioned in fourth playing away to an Instonians that could be caught in mid-table slumber.
Sligo v Naas, Hamilton Park
Player/coach Niall Carson will start on the bench behind what is an unchanged side from last time.
Suttonians v Rainey Old Boys, McDowell Memorial Grounds.
The odds are stacked against the lower mid-table northsiders here as Rainey lead the league with eight wins and a draw.