Armagh Royal strolled into the quarter-finals of the Danske Bank Schools' Cup with a 34-6 win over Campbell College, who became the first seeded team to exit.
RBAI, MCB, Wallace High and Ballymena Academy also all recorded convincing victories, while Enniskillen Royal and Sullivan Upper progressed too - but Friends' and Ballyclare High will have to meet again.
Armagh took some time to gain the upper hand against Belfast opponents Campbell.
Coach Chris Parker said: "The first half was a typical Schools' Cup tie riddled with plenty of errors caused by nerves but Campbell did have their chances with the wind advantage."
The visitors went ahead with a Jack Bonner penalty but Armagh built up pressure around their opponents' '22'. Following a number of phases, Jude Roberts managed to squeeze over.
Romain Morrow goaled and, following a second Bonner penalty, the home out-half replied with one just before the interval to give his side a 10-6 lead.
The second half was a completely different matter with Armagh using the wind intelligently. Morrow added the points to a Ross Taylor try and that was followed with one from Niall Carville.
The best try followed with a move that was started inside their own half. Following a line break by back-row James Agnew, scrum-half Charlie Worth made ground for substitute Josh Cunningham to run in. Morrow again converted before Worth nipped over for the fifth try.
"It was a real team effort so it is very difficult to pick out particular players. I thought Romain Morrow controlled it well at out-half and James Campbell was resolute at full-back," said Parker.
"We knew we were capable of beating them but also felt we would have to be at our best to do so. We did play well and our replacements in the final 20 minutes kept up the momentum."
A fantastic second-half effort earned Ballyclare a 17-17 draw against a Friends' side that had earlier taken a 17-7 advantage.
Ballyclare second-row Jordan Young crashed over for Mark Jackson to goal. The visitors stormed back to take a 10-7 interval advantage when Fergus McEwan scored and full-back Stuart Patterson gathered an offload to run in.
An overlap allowed McEwan to go in for his second but the home team struck back when full-back Mark Jackson outpaced the defence to touch down and back-row Adam Barron's effort was another from close range.
The replay will be on Wednesday.
Results: Ballyclare High 17 Friends' School 17, Armagh RS 34 Campbell College 6, Bangor Grammar 6 Wallace High 33, Grosvenor Grammar 0 Enniskillen Royal 52, RBAI 47 BRA 7, Cambridge Hse 0 MCB 32, Down High 12 Ballymena Academy 51, Coleraine Grammar 17 Sullivan Upper 27.
Schools' Bowl quarter-finals: Belfast High 25 Dalriada 24, Banbridge Academy 19 Rainey Endowed 12, Limavady Grammar 30 Foyle College 0, Portadown College 10 Dromore High 12. Semi-final draw: Limavady Grammar v Dromore High, Belfast High v Banbridge Academy.
Schools' Trophy: Regent House 0 Dungannon RS 40, Wellington College 3 Our Lady and St Patrick's, Knock 5, Larne Grammar 7 Lurgan College 5. Semi-final draw: Dungannon RS v Omagh Academy, OL and St P, Knock v Larne Grammar.