The Lions remain winless for the season after a third successive defeat to a strong Blackheath side.
The visitors opened the scoring early through back row Sloot but this was quickly cancelled out when his opposite number Max Humphreys crashed over from a good Lions driving maul. 'Club' soon regained the advantage just before the quarter mark when full-back Darragh Walsh crossed out wide.
Both sides had been guilty of a number of infringements and firstly Blackheath were reduced to fourteen when Sloot saw yellow for not rolling away but the numbers were soon even again when Lions' Ahren Crowley mistimed a tackle chasing a kick and clearly took the player in the air.
The first half had been a fairly even contest, with both teams missing opportunities to score, but the result was ultimately settled with a try either side of half time for the visitors. Scragg scoring just before the break and a penalty try when a maul was deliberately brought down soon after half time, for which Ben Park also saw yellow.
Although the Lions scored a rather fortunate consolation try through Fred St John, profiting from a misplaced pass that hit a would-be receiver in the face, three maul tries in the final quarter for Blackheath, a second for Sloot followed by scores for Bourne and Harding, gave the Londoners a well deserved victory.
Head coach Gareth Collins commented: ''We were just second best in every area today unfortunately. Blackheath are a top side and their half backs controlled the contest today. More lessons to learn but we need to start learning them fast. The big challenges will just keep coming, starting with Plymouth next week, so it's important we show some resilience in this moment.''
Leicester Lions team:
Patrick, Sterland, St John, Mannion, Stubbs, Bouchier, Ogden, Roberts, Park, Dawson, Britton, Bryan, Evans, Humphreys, Godefroy (c). Replacements: Lamb, Burrows, Smith, Crowley, Afirifah-Mensah.
Blackheath team:
Walsh, Lloyd, Hirsky-Douglas, Hollister, Pollock, Dunford, Burns, Holland, Harding (c), Marsh, O'Sullivan, Scragg, Smeaton, Sloot, Osborne. Replacements: Bourne, Cornish, Jameson, Morley, Briers.
Leicester Lions scores:
Tries: Humphreys (7), St John (69)
Conversions: Mannion (70)
Blackheath scores:
Tries: Sloot (3,60), Walsh (18), Scragg (39), Penalty try (56), Bourne (73), Harding (78)
Conversions: Dunford (4,39,61,74,79)