The Northern teams continued to struggle on the second day of the U15 interpro series in Dublin as the 50-over matches were completed.
Peter Forkin took 7 for 28 to lead the Southern XI to an emphatic seven wicket win over the NCU. Leinster piled on the runs against the NW in a thumping 170-run victory to lead the group.
The Merrion right-arm off-spinner ripped through the NCU innings leaving them in tatters at The Hills.
He weaved his magic as the NCU were dismissed for a modest 147, with number 11 James Lambert top scoring with 20.
Ahmed Shah (2-40) and Cian Egerton (1-14) were the other wicket takers.
James Lambert (2-20) struck twice early, but Leinster opener Andrew Tonge then struck 16 boundaries in an undefeated 88 from just 89 balls as the Southern XI romped to a seven wicket win inside 30 overs.
Luke Whelan (21) and Cian Egerton (17*) also among the runs.
Meanwhile at Rush, Leinster's batsmen were also among the runs, passing 300 for the second match in succession.
This was despite the contest being reduced to 44-overs per side after a delayed start due to a damp square.
Once play got under way Leinster openers Nathan McGuire and Jack McGee enjoyed themselves on their hone ground, sharing an opening stand of 111.
McGuire stroked 11 boundaries in a top score of 62 from only 48 balls, while McGee made 35.
Both fell in quick succession, with NW skipper Robbie Millar taking four wickets.
The runs kept flowing as the hosts showed their batting strength in depth right down the order.
James Forbes hit an unbeaten 51, while Hugo Neville made a breezy 35 in their total of 305 for 9.
In reply the NW innings never gathered any momentum as they were dismissed for 135.
Craig Doherty top scored with 28, while Khayat Bhavsar, Ross McLaughlin and Tom Harpur all made 20's.
The wickets were shared by the Leinster attack, with two apiece for David Vincent, Patrick Morris, Hugo Neville and James Forbes.
Wednesday is a rest day for the competition before the teams switch to T20 mode when the tournament resumes on Thursday.
U15 INTERPRO SCOREBOARDS
At The Hills, Southern XI beat NCU by 7 wickets
S Burke lbw Egerton 9
S Topping b Shah 17
M Humphreys c Whelan b Forkin 18
B Beattie c Tonge b Forkin 19
J Rose c Shetty b Forkin 12
A Wylie c Egerton b Forkin 14
M Daly lbw Forkin 5
A Kennedy b Shah 7
E Wilson b Forkin 1
M Waite st Whelan b Forkin 0
J Lambert not out 20
Extras (3b, 2lb, 1nb, 19w) 25
Total (all out, 40.3 overs) 147
Fall: 1-33 2-42 3-75 4-79 5-107 6-107 7-113 8-116 9-116 10-147
Bowling: C Egerton 8-2-14-1; L O'Reilly 6-0-33-0; A Shah 7.3-0-40-2;
P Forkin 10-1-28-7; H Thompson 8-0-25-0; K Shetty 1-0-2-0.
A Tariq b Lambert 0
A Tonge not out 88
H Thompson c Rose b Lambert 11
L Whelan run out (Daly) 21
C Egerton not out 17
Extras (2lb, 11w) 13
Total (3 wkts, 29.5 overs) 150
Did not bat: L O'Reilly, P Forkin, K McGrane, A Shah, C Sheridan, K Shetty.
Fall: 1-0 2-33 3-91
Bowling: J Lambert 5-0-29-2; M Humphreys 10-3-32-0; A Wylie 6-0-29-0;
J Rose 2-0-16-0; E Wilson 4-0-25-0; M Waite 2.5-0-17-0
At Kenure, Leinster beat NW by 170 runs
N McGuire c Crumley b Millar 62
J McGee c Crumley b Kennedy 35
T Tector c Hall b Crumley 11
C McKay c Bhavsar b Millar 22
B Brownlee run out (Curry/McLaughlin) 26
J Forbes not out 51
M Lynch c Curry b Harpur 21
H Neville b Millar 35
D Vincent c Hall b Millar 3
D Thorne c Kennedy b Crumley 9
P Morris not out 1
Extras (5b, 3lb, 21w) 29
Total (9 wkts, 44 overs) 305
Fall: 1-111 2-113 3-141 4-155 5-178 6-212 7-268 8-288 9-297
Bowling: T Harpur 9-0-64-1; R McLaughlin 6-0-52-0; S Kennedy 9-0-44-1; R Curry 2-0-23-0;
R Millar 9-0-45-4; B Crumley 6-0-50-2; K Bhavsar 3-0-19-0
S MacBeth b Brownlee 0
K Bhavsar c Thorne b Vincent 24
C Doherty c McGee b Thorne 28
R Curry c Brownlee b Forbes 1
K Hall c Vincent b Forbes 7
S Kennedy b Vincent 4
R Millar b Morris 12
R McLaughlin c Forbes b Neville 20
T Harpur c Brownlee b Neville 21
B Higgins b Morris 0
B Crumley not out 1
Extras (4b, 1 lb, 12w) 17
Total (all out, 36 overs) 135
Fall: 1-0 2-39 3-45 4-71 5-75 6-83 7-104 8-122 9-122 10-135
Bowling: B Brownlee 6-0-24-1; D Thorne 6-1-15-1; D Vincent 9-1-31-2;
J Forbes 8-1-15-2; H Neville 4-0-36-2; P Morris 3-1-9-2