They head into the final day of the Premier League level on points with Burnley, but sit one place below the Clarets due to their inferior goal difference.
With their survival out of their hands, there's every chance that Leeds could join Watford and Norwich City in the Championship next season, but Marsch understands that the club will keep faith with his management even if they do face the drop.
Speaking on Friday afternoon ahead of Sunday's clash, Marsch said "I'm still planning to be here even in relegation. It's a long-term project and the club committed to me in that way.
"The connections we have made mesh well together. The support from everyone has been amazing, but I'm not thinking about the long-term project, only about Sunday and preparing for that."
Marsch enjoyed a strong start to life at Leeds, but injury problems mixed with defensive issues mean the Yorkshire side have failed to win in their last five Premier League matches.
In contrast, Brentford have won three of their last five and will know that a win on the final day could see them finish in the top half of the table in their debut campaign in the top flight.
But while Leeds travel to London as underdogs, Marsch's side will be boosted by the return of Patrick Bamford, with the striker having recovered from a foot injury he suffered back in March.
A draw could be enough for Leeds to survive, should Burnley lose to Newcastle at Turf Moor. Kick-off for all Premier League games is scheduled for 16:00 BST, and all possible permutations on the final day can be viewed below...