Bracebridge Heath celebrated another 20-point win to go clear at the top while Market Deeping failed to move off the bottom of the table.
The tightest game was at Spalding where the home side failed by the narrowest of margins to pick up their first victory of the season after putting Sleaford in to bat.
The first wicket fell on nine but from here Sleaford made steady progress to 84-3.
Three more wickets went cheaply before Cameron Hall joined skipper Shaun Morris in a stand of 49 to take the total to 152-7 and Hall was unbeaten on 47 when the final wicket fell on 190.
Spalding’s innings followed much the same pattern with a sixth-wicket stand of 55 between Jonathan Miles and Luke Hollingworth which took them to 138-6.
Hollingworth and Matt Gill helped the score to within 15 of victory but the Sleaford bowlers stuck to their task - Hall taking the final wicket on 185 with three balls of the match remaining.
Bracebridge scored a convincing win over a young Grimsby side who were unable to cope with the bowling of Alex Willerton and Andy Carter.
Matt Lineker hit a polished 65, Matt Carter added 82 and Carl Stubbs got an unbeaten 67 as Bracebridge notched up 318-7.
Lineker and Carter put on 122 for the third wicket after Grimsby had taken the first two wickets for 52 runs while Stubbs and Alex Willerton shared an unbeaten final partnership of 49.
Grimsby quickly found themselves 16-4 but Brendan Volley and Jack Harrison dug in and, when Harrison fell to Willerton, the score had reached 46. Volley continued to attack the bowling, hitting four fours and three sixes and had reached 39 when he ran out of partners with Grimsby’s score on 64, Willerton with 7-43.
The only century of the day came at Grantham where Dan Freeman hit an unbeaten 104 and shared an unbeaten stand of 96 with Dan Webb (60no) to take the home side to 251-4.
Bourne got off to a good start, reaching 90 for the loss of two wickets and with Carl Wilson at the crease runs flowed steadily, the wicketkeeper putting on 59 for the fifth wicket with Quewin O’Connor.
Wilson finally fell to Freeman for 72, making it 225-8 and only six more runs were added before Grantham claimed victory.
Deeping went down to newcomers Alford who now occupy equal third place in the table.
Rikki Bovey hit 83 of Alford’s final total of 243 at Outgang Road and Nick Bennett’s 6-61 helped his team seal victory as the home side were all out for 203.
Last week’s joint leaders Woodhall Spa suffered a surprise defeat at the hands of Lindum who got off to a poor start to the season.
James Kimber took an early Woodhall wicket but Pradeep Chanditha(58) and Henry Wilson added 101 for the second wicket and Prasanna Jayawardene chipped in with 42 to take the total to 220, Jake Benson taking five wickets.
Lindum had reached 59-3 when Will Taylor joined skipper Charlie Tomlinson to add 88 and Tomlinson put on a further 61 with Euan Pickering before being out for 95, leaving Pickering and Benson to take Lindum to victory.
Bracebridge Heath 318-7 (Lineker 65, M Carter 82, Stubbs 67no), Grimsby Town 64 (Willerton 7-43)
Woodhall Spa 220 (Chanditha 58, Benson 5-61); Lindum 222-5 (Tomlinson 95)
Grantham 251-4 (Freeman 104no, Webb 60no), Bourne 231 (Wilson 72)
Alford 243 (Bovey 83), Market Deeping 203 (Bennett 6-61)
Louth 212-5 (Darke 65no), Boston 214-4 (Poole 81)
Sleaford 190, Spalding 185