Glanfield dismissed Langley Manor’s top three as they set about chasing 191 at Ridge Meadow.
Openers Jack Budd (2) and William Budd (6) were removed before Glanfield claimed the wicket of keeper James Purnell (8).
Harding later ripped out the middle order as Langley’s 118-4 quickly became 119-8.
Harding finished with 4-40 - his best SPL figures since 5-33 against the same opponents in May 2017 - as the visitors were dismissed for 130 to lose by 60 runs.
Captain Spencer Le Clercq chose to bat on winning the toss, but he made just nine - the only member of Hambledon’s top seven not to reach double figures.
Ed Moger, batting at No 5, top scored with 46 while there were contributions from Dan McGovern (31), Chris Pratt (28) and Glanfield (22) in a total of 190-8.
Gosport Borough maintained their promotion challenge by chasing over 200 to beat Hythe & Dibden.
Skipper Lee Harrop struck 77 as Borough reached their 202 target with just two balls remaining and seven wickets down.
He was the only member of his side’s top five to reach double figures, with Alex Adams (23) and Mark Toogood (24) - batting at Nos 6 and 7 respectively - making crucial runs.
Gosport still had work to do when Harrop’s departure left the score 142-6, but No 8 Greg Kitchin struck an unbeaten 37 off just 24 balls with four fours and a six.
Gosport are now just a single point adrift of second-placed Hook & Newnham Basics 2nds, with four matches remaining.
Shaun Briggs struck a half-century as Portsmouth & Southsea collected their sixth win in eight completed Division 3 matches.
Having struck two centuries for the 2nds in the Hampshire League this year, Briggs was recently promoted into the SPL XI.
He hit 50 off 54 deliveries as P & S, asked to chase just 113, raced to victory off the first ball of the 24th over.
P & S are now handily placed to capitalise if Hook 2nds or Gosport, the two teams immediately above them, slip up in the closing weeks.
Jack Davies was in a hurry, hitting five fours in his unbeaten 36 made off just 22 balls at St James.
Trojans had earlier found runs much harder to come by after winning the toss.
P & S opening bowlers Jake Peach (0-17) and Jono Willey (0-19) sent down economical seven-over stints.
Kieron Dunstan (2-14), Matt Benfield (2-19) and skipper Ben Saunders (2-19) were all among the wickets as Trojans slithered from 48-0 to end on 112-8.
Skipper Josh McCoy’s third SPL century was in vain as Purbrook slumped back into the relegation zone following defeat to Basingstoke & North Hants 2nds.
McCoy compiled an unbeaten 119 off 99 balls, with 19 fours and a six, as Purbrook totalled 199-8 at May’s Bounty.
George Harradine (36) and No 9 Ian Limb (18) were the only other batsmen to hit more than 12.
It was McCoy’s first SPL ton since his 118 against Gosport three years ago, while his career best remains his stunning 198 for Havant against Ventnor at Steephill five years ago.
McCoy struck early with the ball, dismissing Basingstoke opener Craig Williamson (5). But Josh Coombs (51 not out) then joined Lawrence Benge (73) to add 122 for the second wicket.
McCoy (2-32) dismissed Benge, but Neil Shelar (42 not out) helped Coombs add an unbroken 70 for the third wicket as the hosts sealed an eight-wicket success in the 38th over.
Purbrook, who trail third bottom Hythe & Dibden by just one point, host Portsmouth & Southsea next weekend.