The hosts grabbed two early scores through Charlie Piper and Conrad Cade, Luc Smith converting the latter, before Tykes replied through Tom Davis.
Seramaia Bai added the extras and a penalty around Piper’s second try for 17-10.
But Benji Marfo and Freddie Vaughan bagged braces, Piper completed a treble and Murray Redpath also touched down as Park passed 50, Smith with another conversion and Bill Johnston two.
Louis Guthrie scored a late consolation for Leeds.
Titans and Club maintain momentum
Rotherham Titans remain second following a 33-15 triumph at Birmingham Moseley.
Lloyd Hayes scored a converted try and kicked two penalties for 13-0 before Sam Clarke touched down for the hosts.
A Tighe Maxwell-Whiteley penalty further cut the gap, but Luckas Sableman-Blue’s converted try made it 20-8.
Tommy Taylor added to a Fin Smith score to make it a five-point game, but two more Hayes penalties and an Ellis Thomas seven-pointer sealed the deal for Titans.
Third-placed Blackheath overcame visitors Plymouth Albion 40-28.
Kyle McGhie was on target after Billy Harding opened the scoring, only for Plymouth to hit the front through tries from Jenson Boughton and Bobby Wigginton, Frankie Dart converting both.
Yet Finn Osborne and Harding crossed to put Blackheath 21-14 up at half-time, the lead extended as the former doubled up and Jake Hennessey added to Harding’s hat-trick.
Dart landed after Harry Wilkinson dotted down, Ben Charnock and Albion’s Shea Cornish exchanging seven-pointers to complete the scoring.
Half centuries for Dogs and TJs
Sale FC climbed to fifth with a 58-12 away drubbing of Dings Crusaders.
The hosts struck first via Harry Rowson, Jamie Elswood with the extras, but Sale were 26-7 up at the break as Fergus Mulchrone, Harry Davey (twice) and Corbin Thunder crossed, Joe Green with three kicks.
Davey completed his hat-trick before Ollie Davies and Josh Brown touched down, Green converting the latest.
Stone Priestley-Nangle made it 48-7 before Sam Scott responded for the hosts, Sale having the final word with Davey’s fourth and a Brown second.
Tonbridge Juddians leapfrogged visitors Sedgley Park into seventh after a 56-0 thrashing.
Curtis Barnes, Lewis Gjaltema, Shadyn Osgood and Will Holling secured the bonus-point before the break, Connor Lloyd 100 per cent from the tee.
And there was no let-up in the second half, Lloyd again on target as Barnes reached his hat-trick before Sam Evans completed kicking duties after Tom Kendrick and Dan Laventure touched down.
Clifton leave it late at Lions
Clifton edged hosts Leicester Lions 29-26 thanks to Will Owen’s late try.
A Ricky Cano touchdown put the visitors in front before Lions replied through Ben Park, Luke Bouchier successful from the tee.
Clifton’s Tom Anderson went over before Theo Mannion and Bronson Mellowes pushed Lions further ahead, Bouchier landing for 19-10.
Tom Quinlan converted a Jay Evans try before the break for the visitors, but Jake Sterland and Bouchier made it 26-17 on 53 minutes.
However, Anderson’s second and Owen’s decisive intervention proved key, Quinlan’s boot rubbing salt into the Lions’ wounds.
Rams, meanwhile, dropped to sixth following a 36-29 reverse at Bishop’s Stortford.
