Having made his return to action in midweek, Micky van de Ven was absent from the matchday squad, leaving Spurs with just two senior players available from the bench.
Leading the line was a recently fit-again Richarlison, but he couldn’t stretch far enough to get onto an early searching ball across the face of goal.
The visitors had to endure a period of Brentford pressure thereafter, with Antonin Kinsky’s loose pass leading to a Yoane Wissa header that went just over the bar.
After Kevin Schade wriggled into the box and saw a close-range effort blocked, Wissa again came close from a header, looping his attempt just off-target from Vitaly Janelt’s whipped cross.
Bryan Mbeumo then did well to work some space for a shot that was easily dealt with, but it was Tottenham, somewhat against the run of play, who broke the deadlock with 29 minutes on the clock.
An inswinging corner from Son Heung-min caused Brentford plenty of issues, with Hakon Valdimarsson - making his first Premier League start - unable to assert his authority as Janelt inadvertently bundled into his own net.
The Bees pushed for a response ahead of the half-time whistle, yet clear-cut chances continued to be in short supply.
The Bees had led at the break in just one of their last 11 league games, so it was far from an unfamiliar position for Thomas Frank’s side, who started the second period brightly.
Brentford were still appealing for a penalty when they came within inches of levelling through Wissa, whose improvised shot from Schade’s flick-on clipped the top of the crossbar.
The hosts were persistent in their search for an equaliser, seeing Djed Spence clear Fabio Carvalho’s goal-bound overhead kick, shortly before a late surging run from Pape Matar Sarr was picked out by Son, allowing the substitute to slot home and seal a crucial victory for Spurs.
Despite opening the scoring on seven occasions, this marks just a second league win in 12 matches for Ange Postecoglou (D2, L8), who sees his side climb two spots to 14th, easing concerns of a previously unthinkable relegation battle.
As for Brentford, a fifth league encounter without a win at the Gtech Community Stadium leaves them 11th, with the prospects of European qualification beginning to fade for a side that appear destined for midtable obscurity.
Flashscore Man of the Match: Djed Spence (Tottenham Hotspur)