Rebecca Barry cancelled out Liz McInerney’s opener for Monkstown and Yvonne O’Byrne gave Quins a 2-1 half-time lead with six cards already having been shown.
But Chloe Watkins’ corner sweep tied it again and although Quins had big chances through O’Byrne and Karen Bateman, Evans won it in the dying seconds for Town when her reverse deceived Quins netminder Emma Buckley.
Monkstown now have a two-point lead at the summit while UCD have leapfrogged Quins into second after dispatching Pegasus 3-2, a result that leaves a six-point gap between the top three and the chasing pack.
In the Irish Trophy, it was a mixed day for Munster sides as 2014 and 2015 champions Cork Church of Ireland advanced thanks to a 2-0 success against Rathgar, but Waterford lost a thriller 4-3 at Rainey.
The sole Munster Division 1A game saw Catholic Institute move into top spot with a 1-0 success over Ashton. It was far tighter than last week’s 4-0 drubbing but the Cork ladies still left empty-handed thanks to Kym Daly’s late winner.
Julian Dale celebrated his midweek call-up to the Ireland squad with a six-minute hat-trick in second-placed Cork Church of Ireland’s 3-1 win over Instonians in the men’s EYHL. Another new Irish panellist, Luke Madeley, bagged a brace as Three Rock’s resurgence continued with a 2-0 success at Railway Union.
Banbridge went top as Matthew Bell’s 53rd minute penalty stroke saw them beat their Co Down rivals Lisnagarvey 1-0 at Comber Road, a first defeat in 24 games for the champions.
Elsewhere, Monkstown were comfortable 4-1 winners over Pembroke while Glenanne notched the result of the weekend, twice coming from four goals down to tie 5-5 with a UCD side that continue to be the league’s great entertainers with floods of goals at both ends.
Domestically, Bandon have a three-point lead at the summit of Munster’s Division 1 after routing Cork C of I B 5-1. Ashton and Harlequins drew 1-1 for the second week running to move the former up to third, with Limerick’s 3-2 win over UCC leaving the students bottom of a tightly-packed table.