Lewandowski started against Real Betis on Sunday with the captain's armband, was substituted to a thunderous standing ovation in the 84th minute, and was then tossed into the air by teammates before walking through a guard of honour formed by the squad.
He addressed supporters directly from the pitch after the final whistle as Barcelona completed a 3-1 victory and capped a perfect home record of 19 wins from 19 La Liga matches at the Camp Nou this season.
Yuste spoke to journalists after landing in Gran Canaria for the Copa de la Reina final, making clear the scale of what Lewandowski's four years have meant to the club.
"He arrived as a star and leaves as a legend. I met him in the United States four years ago when he joined Barcelona and from the very first day he demonstrated exemplary professionalism.
"He has helped enormously, especially the younger players. He is a tremendous footballer, who has always looked after himself to the maximum, who has given absolutely everything for this badge and who, for me, is one of the best number nines in the history of football. His experience and leadership have been fundamental for a squad as young as ours. I can only have words of gratitude towards him."
Lewandowski scored 119 goals in 192 appearances across four seasons in Catalonia, winning three La Liga titles and one Copa del Rey. He was set to leave when his contract expires this summer, with Barcelona having offered a one-year extension at a reduced salary that the 37-year-old decided to decline in favour of a new challenge.
On the transfer market, Yuste declined to be drawn on specific targets to replace the Pole, instead expressing confidence in sporting director Deco and the club's financial trajectory.
"We have a great technical director in Deco and I am convinced he will know perfectly what decisions to take for the future. As for the 1:1 rule, the technical, financial and sporting departments are doing excellent work that makes me very optimistic."