They ran out eight-wicket winners in Sunday’s final at the Riverside, where bat dominated ball throughout.
Garstang had opted to bat first and closed their innings on 248-8 from 40 overs.
Michael Walling (55) and Matt Crowther (64) added 103 for the second wicket before Ian Walling provided further impetus down the order.
He hit five sixes and a four in reaching 42 from only 22 balls, setting up a sizeable target for Blackpool to chase.
They did so, reaching 249-2 with 20 balls remaining after the departures of Tomas King (21) and Kasim Munir (13).
That left them 49-2, only for Shivam Chaudhary and Josh Boyne to add an unbroken 200 for the third wicket.
Chaudhary struck four sixes and as many boundaries in reaching 97 not out from 95 deliveries.
He was overshadowed by Boyne, who followed up his 2-36 with an undefeated 110: an innings which took only 87 balls, including 10 fours and four maximums.
Sunday’s win helped to atone for a disappointing league defeat at Leyland the day before.
Blackpool lost by 111 runs after being skittled for 62 in chasing their hosts’ 173-8.
Boyne collected 3-36 during the Leyland innings, in which Andrew Makinson top-scored with 39 and Zak Willox added 37.
However, Blackpool were all out inside 27 overs of their reply after collapsing from 15-0 to 35-8.
Andrew Jacques was the man responsible, running through the top order on his way to figures of 6-28.
King had made 15 but the main resistance came from Matt Grindley as he top-scored with 19.
It means Blackpool cannot catch fourth-placed Longridge and could be overhauled by Leyland with a heavy defeat against Eccleston on the final day.
Elsewhere in the NPCL, Fleetwood were unable to halt Chorley’s charge towards a first title in 43 years.
Chorley won Saturday’s penultimate fixture by eight wickets and lead second-placed Kendal by three points.
Fleetwood were asked to bat but had to settle for 107 all out, skipper Adam Sharrocks hitting 40.
Wicketkeeper/coach Atiq Uz-Zaman added 29 but no-one else reached double figures as Sam Steeple took 3-33.
Fleetwood bowlers Declan Clerkin and Rizwan Patel had a couple of early successes, removing openers Will Moulton and Alfie Dobson.
Josh Pistorius (47 not out) and professional Roshen Silva (27 not out) then dug in as Chorley wrapped up victory on 110-2.
Fleetwood, two points behind sixth-placed Leyland, could climb into the top half with a positive result at relegated Penrith.
St Annes leapfrogged Fulwood and Broughton into ninth position thanks to a 42-run win at Highfield.
Having been asked to bat first, St Annes were reduced to 43-5 before skipper Nathan Armstrong (35) and Lukman Vahaluwala (38) added 74 for the sixth wicket.
That was crucial in pushing St Annes towards their eventual 148 all out as Hareen Buddila took 4-29 and Khalil Patel 4-43.
Fulwood and Broughton’s reply saw them all out for 106, Vahaluwala following up his batting efforts with 6-17 from 13 overs.
St Annes are back at Vernon Road on the last day when they host Netherfield, knowing victory could see them overhaul their visitors.
In the Liverpool Competition, Lytham CC’s fourth straight win has them firmly in the First Division promotion fight.
An all-round display yielded a 128-run victory and maximum points against Old Xaverians.
Batting first, Lytham slipped to 17-2 before eventually declaring on 225-7 from 55 overs.
Guy Roberts (63) and skipper Matt Taaffe (27) added 90 for the third wicket, with Tom Jefferson (33) and Avinash Yadav (28) also contributing.
Ian Carroll took 4-48 for the visitors, who were shot out for 97 in reply having been 21-5 at one stage.
It was very much a one-man show as Daniel Harrison smashed seven sixes and two fours in a 39-ball knock of 75.
He eventually fell to Jack Saunders (3-20) as Yadav took 4-56 and Richard Openshaw 3-21.
Victory leaves Lytham third, a point behind second-placed Birkenhead Park and three ahead of Spring View in fourth with two games to go.
The first of those is on Saturday when they travel to third-bottom Caldy.
In the Moore and Smalley Palace Shield Premier Division, Thornton Cleveleys were no match for a determined Vernon Carus, who eased their relegation fears with a nine-wicket home win.
TC were put in and dismissed for 65, Oliver Kyle their top scorer with 22.
He wasn't the only one to find Jacob Holland unplayable as the Vernons bowler took a remarkable 5-10 from his 11 overs, presiding over a collapse from 38-2 to 41-7.
Daniel Howard was the only TC bowler to take a wicket as opener Ian Dunn rushed his side to victory with an unbeaten 32 from 21 balls.
That win was sealed at 66-1 in just 7.4 overs, lifting Vernons 12 points clear of the bottom two with two rounds of matches remaining.
Fifth-placed Thornton Cleveleys’ final home fixture of the season is a Fylde coast derby with relegation-threatened Kirkham and Wesham on Saturday.
They are level on points with second-bottom Torrisholme – and only 11 clear of bottom club Morecambe – after losing by eight wickets to promotion hopefuls Carnforth.
Batting first, K&W collapsed to 5-5 and then 41-8 before eventually being dismissed for 71, Tait Roberts-Hodgson and Andrew Hogarth both making 16.
Darren Nelson took 6-27 for Carnforth, who breezed to 73-2 inside 17 overs of their reply.
Great Eccleston are sixth following their 17-run victory in a low-scoring match at Preston.
Great Ecc batted first and were limited to 118-9 before bowling out their hosts for 101 in reply.
Jim Procter took 5-27 for the away team, which hosts champions Euxton on Saturday.