Pembroke hit the front on 30 minutes when Irish international defender Tim Lewis deflected home Sothern’s drag-flick, but Quins were level four minutes later when Dan Hobbs beat David Harte with a precise drag.
Despite being down to nine players at one stage, with both Gordon and Maurice Elliot in the sin bin, Pembroke went back in front on 45 minutes when Sothern rifled home a drag-flick.
Cork Church of Ireland made hard work of their home tie against Fingal, but their superior fitness told in the second half as they cruised to a 6-2 win.
The visitors took a shock lead on seven minutes when Adrian Sweeney tapped home Eamonn Bane’s cross, but C of I were level within five minutes thanks to a stunning strike from Andy Herbert, who directed a diving reverse home from the edge of the circle.
John Jermyn roofed a drag-flick from a short corner on 24 minutes to give the hosts the lead, but the Airport side equalised three minutes later through Paddy Gahan.
But C of I simply owned the second half, with the visitors clearly out on their feet after their exertions in the first period, with Jermyn adding two copycat drags to complete his hat-trick, while David Hobbs and Roger Gray gave the scoresheet a flattering look.
Three Rock Rovers earned a modicum of revenge for their Irish Senior Cup exit at the hands of Monkstown last season, eventually running out 4-2 winners at Grange Road.
The Glenageary outfit looked to have snatched a draw when they reeled in a 2-0 deficit, but late goals from Irish internationals Phelie Maguire and Peter Blakeney gave Rovers the win.
In the Ulster derbies, Banbridge ousted old rivals Lisnagarvey 2-0 thanks to Ross McCandless and Simon Magowan strikes, but Cookstown and Glenanne were held to 1-1 draws by Instonians and Annadale respectively.
In the women’s IHL, Cork Harlequins withstood a late surge from Ballymoney to claim a hard-earned 1-1 draw after Cliodhna Sargent had cancelled out Bridget McKeever’s opener.
Cork C of I’s lack of a clinical finisher again looked set to haunt them as they spurned a hatful of chances at home to Randalstown, but Mel Ryan made one penalty corner effort count to secure a 1-0 win.
Elsewhere, Louisa Moore underlined her importance to Pembroke Wanderers’ cause when she struck the winner six minutes from time as the Dubliners defeated Armagh 2-1 at Serpentine Avenue.
Kate McKenna’s second-minute strike for Railway Union gave Pegasus a fright at Jordanstown, but they recovered to win 2-1 thanks to Suzanne Beaney and Kirsty McCollum.
Linda Caulfield’s double helped Hermes to a 3-2 win over UCD, while teenager Zara Delany grabbed a hat-trick inside the first 10 minutes as Loreto beat Belfast Harlequins 5-2.