BALLYNAHINCH v GARRYOWEN, Ballymacarn Park, 2.30pm
So will Ballynahinch claim their third Division One scalp in this season's tournament or will Garryowen reach the final for the second time in three seasons?
Cup winners in 2007, Garryowen have been going great guns of late in the AIB League, racking up nine successive wins since drawing with Shannon in October.
But having to play St. Mary's College in a refixed league tie on St. Patrick's Day will test their squad's strength in depth as this weekend's trip to County Down is their second match in five days.
Garryowen coach Dara O'Sullivan boasts a settled side and it will be interesting to see how many enforced changes he makes following last Tuesday's hard-fought 9-8 win over Mary's.
Gerry Hurley had a great game at Templeville Road, making his comeback from a long injury lay-off and his presence could be crucial at the light Blues face into the business end of the season.
As ever, full-back Conor Kilroy will be called upon to land the place-kicks for the Limerick side and it will be interesting to see how he fares against Ballynahinch number 10 Ryan Bambry.
This has been the season of seasons for 'Hinch so far and Derek Suffern's men show no signs of stopping just yet.
Adding to the feelgood factor at Ballymacarn Park, where the Ulster Senior League trophy is residing for the first time, Nevin Spence and Michael Kirkwood bounced back from long term knocks to feature in an 83-0 Ulster Senior Cup thumping of Rainey Old Boys last weekend.
During that runaway win, Suffern took the opportunity to replace a number of his key players in the second half and 'Hinch will undoubtedly be the fresher team come kick-off time.
Garryowen's greater cup experience, top flight status and canny knack of pulling off tight wins suggests they stand a good chance of progressing through to next month's final.
But 'Hinch, winners over Shannon and Galwegians in earlier rounds, will not fear the Limerick giants.
They will relish the chance to dispose of O'Sullivan's impressive side and we feel they will just edge it, possibly with another late kick from classy New Zealander Bambry.
Supporters are advised to travel to Ballymacarn Park in good time as a big crowd is expected, with plenty of entertainment on site in the form of the clubhouse and a large marquee, in which there will be large TV screens showing the Wales v Ireland match afterwards.
There will also be face-painting and a barbecue in full swing throughout the day.
AIB League Position: 3rd in Division Two
AIB League Form (last five matches, latest on the right): L (13-10 away to Lansdowne), L (21-9 away to UCC), W (31-5 at home to Malone), W (46-15 away to Bective Rangers), W (23-13 at home to Dublin University)
AIB Cup Run: 2008/09 - First Round: Naas 20 Ballynahinch 41, Forenaughts; Second Round: Ballynahinch 33 County Carlow 10, Ballymacarn Park; Third Round: Shannon 14 Ballynahinch 15, Coonagh; Quarter-Final: Galwegians 22 Ballynahinch 26, Crowley Park
AIB Cup History: 2005/06: Did not qualify; 2006/07: Did not qualify; 2007/08: Reached second round
AIB League Position: 2nd in Division One
AIB League Form (last five matches, latest on the right): W (22-15 away to Terenure College), W (20-18 at home to UL Bohemians), W (14-7 away to UCD), W (20-13 at home to Young Munster), W (9-8 away to St. Mary's College)
AIB Cup Run: 2008/09 - Second Round: Garryowen 37 Thomond 13, Dooradoyle; Third Round: Bective Rangers 9 Garryowen 15, Donnybrook; Quarter-Final: Garryowen 28 Buccaneers 17, Dooradoyle
AIB Cup History: 2005/06: Semi-finalists; 2006/07: Champions; 2007/08: Quarter-finalists
IrishRugby.ie Prediction: Ballynahinch to win by less than 7 points
YOUNG MUNSTER v CORK CONSTITUTION, Tom Clifford Park, 2.30pm
Cork Constitution's AIB League and Cup double bid is sure to come under pressure on Saturday when they take on Young Munster at Tom Clifford Park.
The Leesiders, who battled their way to a 16-9 Division One win over Shannon last Tuesday, resume their cup campaign with a tricky semi-final trip to Limerick.
Young Munster managed to beat Con 21-16 at Temple Hill in October, handing Brian Walsh's men their first league defeat since January 2008, so they will claim to have the psychological edge.
Of more pressing concern for Mike Lynch's charges is their second-from-bottom positioning in the Division One table, but the cup run is much more than a welcome distraction.
Munsters may have lost four of their last five league games but home advantage has helped them make serious progress in the AIB Cup.
In previous rounds, Belfast Harlequins, UCD and UCC have all come away from Tom Clifford Park with defeats to contemplate and Munsters will be relishing the prospect of a big giant-killing act this weekend.
Full-back Matthew Costelloe, AIB Club international winger Derek Corcoran and the Munster-contracted Mike Prendergast are the key backs for Young Munster.
Up front, Lynch has had some big performances in recent weeks from front rowers Ger Flaherty and Ger Slattery, second row Darragh Payne and tireless number 8 Mark McHugh.
Cork Con coach Walsh may have to employ a squad rotation system after his side's attritional outing against Shannon on St. Patrick's Day.
But Con's pursuit of two All-Ireland trophies has been aided by the number of Munster-contracted players at their disposal and the emergence of younger players like winger Simon Zebo and full-back Peter Brougham.
For those reasons and given their recent form, Con will be confident of ending Young Munster's hopes of reaching next month's cup final.
No landslide victory but the 2006 champions should have enough in the tank to make it through to the April 4 decider.
Young Munster -
AIB League Position: 15th in Division One
AIB League Form (last five matches, latest on the right): L (15-10 away to Galwegians), W (15-3 at home to Terenure College), L (33-19 away to Blackrock College), L (28-10 at home to Shannon), L (20-13 away to Garryowen)
AIB Cup Run: 2008/09 - Second Round: Young Munster 18 Belfast Harlequins 15, Tom Clifford Park; Third Round: Young Munster 27 UCD 26, Tom Clifford Park; Quarter-Final: Young Munster 12 UCC 10, Tom Clifford Park
AIB Cup History: 2005/06: Did not qualify; 2006/07: Did not qualify; 2007/08: Beaten in first round
Cork Constitution -
AIB League Position: 1st in Division One
AIB League Form (last five matches, latest on the right): L (20-19 away to Garryowen), W (25-19 away to UL Bohemians), W (49-3 away to Dungannon), W (47-7 at home to Buccaneers), W (16-9 at home to Shannon)
AIB Cup Run: 2008/09 - Second Round: St. Mary's College 13 Cork Constitution 15, Templeville Road; Third Round: Bruff 10 Cork Constitution 22, Kilballyowen Park; Quarter-Final: Dolphin 16 Cork Constitution 18, Musgrave Park
AIB Cup History: 2005/06: Champions; 2006/07: Reached first round; 2007/08: Reached third round
IrishRugby.ie Prediction: Cork Constitution to win by more than 7 points