Sanchez joined McLaren from Ferrari in January among a series of hires to augment the team's engineering staff, but it became apparent that his duties as the technical director in charge of concept and performance were "not aligned" to those discussed previously.
Team principal Andrea Stella will thus assume Sanchez's duties in the interim, as the team searches for a replacement to head up the performance side of the team.
In a statement, Stella remarked that he was grateful for Sanchez's contributions among his short period at the team, but recognised that the initial brief laid out had not translated into the reality of the job.
"Following thoughtful discussions between David Sanchez and the team leadership, the mutual decision has been taken for David to leave the team," Stella said.
"Upon our joint reflection, it became apparent that the role, responsibilities, and ambitions associated with David’s position did not align with our original expectations when he agreed to join us in February 2023.
"Recognising this misalignment, both David and I agreed that it would be best to part ways now, so to enable him to pursue other opportunities that will better leverage the full scale and breadth of his remarkable skillset.
"We greatly and gratefully value the contributions that David has made during his relatively short time with us, and we wish him the best in his future endeavours."
The departure of Sanchez has instigated a number of changes, as ex-Red Bull engineer Rob Marshall now assumes the position of chief designer.
Neil Houldley takes over the reins from Marshall as technical director of engineering, while Peter Prodromou remains in place as technical director of aerodynamics.
Sanchez had started his F1 career with Renault before moving to McLaren in 2007 as a senior aerodynamicist, remaining with the team during Lewis Hamilton's first championship-winning year.
The Frenchman moved to Ferrari in 2012, remaining with the Prancing Horse for over a decade before signing a deal last year to join McLaren for the start of 2024.
"I am grateful for the opportunity to have been a part of this team," Sanchez stated.
"While the role we envisioned and had agreed to was not aligned with the reality of the position I found, I leave with respect for the leadership, admiration for the dedication of my colleagues, and appreciation for the openness and honesty in which we discussed and arrived at this decision.
"I wish this team continued success as it continues its journey to the front of the grid where it belongs. I look forward to my next challenge within F1.”
