A game-changing goal from captain Beth Towle and hat-trick by Amy Lake saw the Laces win their Division 3 South title-decider with London Academicals, who had scored through Emily Sprake.
The Clapham Common-based Laces (pictured right), playing in their first season together, finished three points ahead of the Accies.
The fixtures in Division 2 North also brought together title rivals in the last game of the season, with Battersea & Hammersmith needing to defeat New London Lionesses (pictured top) to take the top spot from them.
But while Antonia Cole netted a hat-trick for the hosts, it was not enough, as a goal from Sarina De Almeida Franco and a brace by Kizzanna Fergus earned a championship-winning 3-3 draw for the Regents Park-based Lionesses.
Both sides are in the Greater London League Trophy semi-finals on 9th April, when the Lionesses vist Ashford Town (Middx) for a 2pm kick-off and Battersea meet Putney Vale at the Richardson Evans Memorial Playing Fields, 12.30pm.
On the same day, London Academicals have a Sue Sharples Memorial Trophy semi-final away to Hsckney Reserves, on the Marshes at 2pm.