Harrowby hit six goals in front of their biggest crowd for a number of years.
Two early goals left the Gingerbreads chasing the game at Hyde on Tuesday night.
The Gingerbreads were second best all afternoon and ended up thrashed by a Lancaster City side who just had too much time throughout the 90 minutes.
Goals at key moments in the game saw Grantham Town start their season's home campaign with a defeat against a side fancied for promotion.
After 971 days, the Gingerbreads finally recorded a win on the road in the league.
A football club has shown its ambition with plans to extend its facilities.
A man who founded a local football club turned 100 today.
Harrowby United welcomed a strong looking Spalding United team who play two leagues higher.
Two second-half goals won the game for Cleethorpes Town on Saturday after they were the better side for a lot of the game.
Despite missing five regulars, Harrowby United battled well in hot conditions against a higher placed opponent.
Grantham's first home pre-season friendly ended in disappointment, but new manager Carlton Palmer took positives from the game.
Former Grantham Town manager John Wilkinson's death was announced by Lincoln United on Friday evening.
Harrowby United entertained another higher league team in Boston Town for their second friendly game on Saturday.
Streets in Grantham were deserted last night as football fans watched England play against Italy in the Euro 2020.
Hundreds of people in our area have signed a petition calling for a Bank Holiday on Monday if England win Euro 2020.