Fahad Masood equalled the Lincolnshire Premier League record of 67 wickets with three games to go, taking 5-30 in Bourne's winning draw at Hartsholme.
Masood also scored 70 and Ben Stroud 72 in Bourne's 251-8, with the hosts reaching 102-8 in reply.
With leaders Bracebridge Heath's match at Market Deeping rained off, Bourne and Boston were able to gain ground.
Jonny Cheer (101) and Matt Ward (70) helped Boston to 226-3d in their 58-run victory over Grimsby.
In reply Grimsby were all out for 168 despite an unbeaten 87 from George Linde.
Sleaford trounced bottom side Nettleham by 195 runs with Prabodha Senevirathne making 125 in the hosts' 285-8 before Steve Bradford took 6-20 to dismiss the visitors for only 90.
Pakistan international Fawad Alam scord 100 as Woodhall Spa claimed a winning draw in their relegation clash with Skegness. Sam Evison also weighed in with 71 in Woodhall's 287-7 with Wade McCall top-scoring on 75 in Skegness's reply of 234-7.
Louth's match against Lindum fell victim to the weather with only six overs of play possible before the game was abandoned.
LINCOLNSHIRE PREMIER LEAGUE
Results for Saturday, 27 August
Abbey Lawn: Bourne 251-8 (Stroud 72, Masood 70); Hartsholme 102-8 (Masood 5-30)
The Mayflower Ground: Boston 226-3 dec (Cheer 101, Ward 70); Grimsby 168 (Linde 87no)
London Road: Sleaford 285-8 (Senevirathne 121); Nettleham 90 (Bradford 6-20)
Jubilee Park: Woodhall Spa 287-7 (Alam 100, Evison 71); Skegness 234-7 (McCall 75no)
London Road: Louth v Lindum - Louth 29-1; abandoned after six overs
Outgang Road: Market Deeping v Bracebridge Heath abandoned with no play