At the bottom of the table, Grimsby picked up valuable points as Louth failed by just three runs to reach their target.
And at Woodhall Spa, it was all action with a 1940s weekend in full swing in the village, an innings of 299 for seven from Bracebridge Heath and a maiden century in senior cricket for Jack Timby.
Obus Pienaar needs just 10 runs to reach 1000 for the season - if he achieves this next week it will be the quickest 1000 in the league’s history - but the South African’s unbeaten 125 off 91 balls against Grantham was no guarantee of victory.
His stands of 60 with Tom Shorthouse and 79 with Oliver Burford took the home side to 270 for six at the close, but solid batting down the order saw Grantham edge ever closer to their target.
From 130 for three, Dan Webb (73) and Matthew Wing added 92 and Wing was unbeaten on 65 when the visitors claimed a five wicket win with just five balls of the match remaining.
This keeps Grantham in touch with the leaders, six points behind third placed Sleaford, while a much lower scoring game saw Market Deeping go top, six ahead of Bracebridge Heath.
Having invited Lindum to bat, Deeping’s bowlers kept the pressure on their opponents and from 111 for five, Lindum were reduced to 115 for nine then 124 all out, Zac Simmonds taking three wickets for two runs off 20 balls.
Deeping set off well, Nick Green and Ali Sharp putting on 49 for the first wicket but three wickets for Tom Lindsay helped trigger a collapse to 88 for five.
Jonny Miller also took three wickets but from 112 for eight, David Sargeant and Lee Peacock saw their side to victory.
David Whapplington again proved his worth as an opener with an innings of 85 at Woodhall Spa while Brett Houston hit 50 and Matt Carter was run out on the last ball of the 50 overs for 95.
This took the visitors to 299 for seven and Woodhall’s pursuit set off well before a flurry of wickets saw them go from 94 for one to 115 for five to slow the run rate.
Opener Jack Timby held the innings together with some patient batting, celebrating his maiden century at senior level before being out with the score on 202 and only seven runs were added before the innings closed with seven wickets down, Matt Bradley taking five for the visitors.
Jack Berry put in a man of the match performance for Bourne, taking seven Boston wickets for 62 runs to restrict the visitors to 203 for nine, Jonny Cheer hitting 86.
Berry then opened with Rob Bentley, hitting 52 and from 103 for two, Carl Wilson and Sam Evison saw Bourne home with 55 and 52 respectively.
Skegness avoided the relegation zone after Nettleham collapsed from 114 for one to 149 all out chasing the home side’s 164 of which Dylan Labuschagne hit 62.
Rhett Bridgens then hit 53 and shared a second wicket stand of 95 with Adi Sreedharan (41) but from here, Nettleham tumbled to defeat, Ray Jordan and Pradeep Chanditha each taking three wickets.
Grimsby moved up off the bottom and are now only six points behind Skegness after a nailbiter at home to Louth.
Having lost a wicket off the first ball of the match, Grimsby recovered quickly as Neal Snell and Steve Crossley put on 88 and Crossley (89) and Lee Charlton then put on 106 for the fourth wicket.
Charlton was out for 92 as the innings closed in 245 for five.
Louth got off to a better start with an opening stand of 74 between Seb Darke and Laurence Scott who hit 51 and steady batting down the order kept the scoreboard ticking over.
The introduction of Michael Brown and Harrison Tice to the attack brought wickets, the bowlers taking three each but lower down the order, Tom Corden and Nick Keast added 33 for the eighth wicket.
When Keast was out, Louth had 232 on the board but the overs ran out with the visitors still three short of their target.
Results: Boston 203-9 (Cheer 86, Berry 7-62), Bourne 204-2 (Berry 52, Wilson 55no, Evison 52no); Grimsby 245-5 (Charlton 92, Crossley 89), Louth 242-8 (Scott 51); Bracebridge Heath 299-7 (Whapplington 85, Houston 50, Carter 95), Woodhall Spa 209-7 (J Timby 100, Bradley 5-57); Lindum 124 (Thomas 54), Market Deeping 125-8; Sleaford 270-6 (Pienaar 125no), Grantham 271-5 (Webb 73, M Wing 65no); Skegness 164 (Labuschagne 62), Nettleham 149 (Bridgens 53).