Old Lincs won the toss and batted on a very indifferent track.
Wickets fell at regular intervals and the home side were bowled out for 100 on the dot.
Will Broughton was outstanding and took four wickets.
He was excellently supported by Rich Hickling (2), Tom Hackett (2), Tom Johnson, a superb direct hit run out from Liam Evans and a stunning slip catch from skipper Rob Bee.
Bee and Jonny Clark got the reply underway and battled well against some excellent bowling and, of course, the varying bounce of the pitch.
The opening partnership reached 49 when Clark went lbw for 26.
Bee went soon after for 23 and this brought about a cluster of wickets leaving the game in the balance.
A brilliant little partnership between Liam Cotton (11) and Jack Thompson (7) got Horncastle back on track and nearly saw them home.
A couple of well hit boundaries from Hickling (10 not out) got the side over the line to win by three wickets.
This was a fantastic effort from the team as a whole and a brilliant victory.