After picking up their first victory in four weeks the previous week, Boston made the trip to second-placed Grantham on Saturday.
Grantham had lost only two games in 2018 and are challenging Bracebridge Heath for the Lincolnshire ECB Premier League title.
Winning the toss, Grantham’s captain Dan Webb had no hesitation in opting to bat first on a pitch that looked hard and flat with an outfield that looked quick.
It could have been completely different if Carnelly hadn’t have been dropped off the first ball of the innings.
Fell was dismissed by Ishan Jayaratne after a smart catch from Musson.
This brought Dowman to the crease to join Carnelly and the pair batted sensibly, but aggressively, to push the scoreboard along.
The pair put on 120 before the return of Jayaratne saw Carnelly edge behind to Michael Musson on 58.
Baxter then caught Dowman for 70 off the bowling of Jayaratne, but another partnership between Freeman and Webb took Grantham to maximum batting points, before Webb fell to Deans.
With Freeman and Dobson the putting on another 60 valuable runs, Boston found themselves up against it as Grantham went on to score 306-5 off their 50 overs.
After the tea interval, it became an even bigger task as Ben Troops and Sam Holland were both dismissed by Dowman, bringing Jonny Cheer and Jayaratne together at the crease.
The pair batted sensibly while keeping up with the rate and their partnership of 110 was dominated by Jayaratne, who contributed 80 of those runs before being stumped off Dobson after the ball ricocheted off the pads of Wing.
Cheer was next to fall after mis-timing straight to deep square leg for 66.
The Grantham bowlers were back on top now and Musson (13) and Baxter (22) were dismissed by Keast and Dowman to leave Boston 213-6.
Lawson and Tetther took Boston past the maximum batting points total before Dobson and Freeman picked up a wicket each to leave Damian Lawson and Scott Elleray to bat the remaining overs to see Boston finish on 247-8 from their allotted overs.
Boston picked up seven points but have now dropped to eighth place in the Lincolnshire ECB Premier League.