Dave Heffernan's side have 30 points from their three matches - one better than Boston A who have a game in hand.
Only Kevin Vinter's rink came away empty-handed though they out up a stubborn fightback after trailing 3-17, pegging back 15 shots in nine ends before eventually losing 18-21.
Rink honours went to Tony Barwell, Neil Crees, Dusty Miller and Roger Martin whose aggregate seven shots on the 19th and 20th ends proved crucial.
Scores: Lincs Over 60s League (South): Stamford 96 (12 pts) Sleaford 61 (2). Stamford names only: T Barwell, N Crees, D Miller, R Martin won 28-12; B Crouch, C Jones, P Burt, B Warters won 27-10; R Blake, D Henshaw, Mal Smith,T Christie, 23-18; D Heffernan, K Gentry, K Rippin, K Vinter lost 18-21.
Northants A play Northants B at Stamford IBC on Sunday in the opening salvo of the English Bowling Federation's 2021-22 inter-county Derbyshire Trophy (10 am). All the players who qualify are attached to local outdoor clubs.
A TEAM: Paul Dalliday, Michael Jeapes, Simon Law; Brian Martin, James Harford, Tristan Morton; Wayne Morris, John Earl, Martyn Dolby; Michael Humphreys, Adam Warrington, Roger Martin.
B TEAM: Stuart Agger, Cliff Watson, Graham Agger; Les Sharp, Neil Wright, Paul Bailey; Gareth Dickenson, Brian Bassam, John Holroyd; Andy Cox, Mick Greaves, Mick Linnell.
The shop will be open from 11am to 7pm and carries a full range of bowls together with an extensive offering of bowls clothes, shoes and equipment.
Not only will you have a good choice of things to buy, remember Christmas is only just around the corner, but you will be able to get advice from one of the World's best indoor players