Toulouse had scored 106 points in their past two away trips, including a 46-0 whitewash of St Helens, but it was their turn to be scoreless on this occasion and they remain ninth after a 14th defeat of the campaign.
Ned McCormack was denied a sixth-minute score for Leeds in a stop-start opening when video referee Liam Rush spotted Chris Hankinson’s knock-on.
But the Rhinos had the lead after 12 minutes when Connor dummied and cut back inside to score following Lumb’s break.
Super League’s leading points scorer this season was involved again as he teed up Oledzki to power over from close range.
Without injured playmaker Olly Ashall-Bott and fielding six academy graduates, Toulouse could not capitalise on good positions, with Tiaki Chan’s surge halted five metres short after Luke Polselli’s brilliant one-handed offload.
And Leeds pulled further clear when Presley Cassell’s fine offload gave Holroyd a simple finish under the posts.
The hosts began the second half with more intent and within minutes, quick ball through the hands saw Croft send in McDonnell for his fifth try in three games.
Holroyd was held up over the line, while last-ditch defence denied Jarrod O’Connor and Lumb as Toulouse, to their credit, continued to fight.
But the incessant pressure told when Newman, playing just his third game on the wing in place of the injured Maika Sivo, went in at the right corner.
Connor, the 2025 Man of Steel, leapt high to grab Lachlan Miller’s pinpoint kick under the posts and register his second score.
With the game long since won, Leeds rang the changes but still pressed for more.
Croft sniped through a gap for his 24th Super League try of the season, and Lumb finished in the left corner, before Connor’s touchline conversion typified a clinical all-round display from the leaders.
Leeds: Miller; Lumb, McCormack, Bird, Newman; Croft, Connor; Oledzki, O’Connor, Jenkins, Hankinson, McDonnell, Watkins.
Interchanges: Smith, Lloyd, Cassell, Holroyd.
Toulouse: Polselli; Laguerre, Tropis, Quai-Ward, Ulberg; Collin, Rouge; Butler, Marion, Belmas, O’Kane, Jassaume, Cator.
Interchanges: Garrigues, Chan, Toleafoa, Wallace.
Referee: Tara Jones.
