The 33-year-old was substituted to a standing ovation at Camp Nou as his side maintained their unbeaten campaign after a 2-2 draw against their fierce rivals, despite being reduced to 10 men.
Luis Suarez opened the scoring early on but Cristiano Ronaldo hit back immediately, before Sergi Roberto was shown a straight red card for hitting Marcelo just before half-time.
But Barca responded after the restart as Lionel Messi reclaimed the lead for the hosts, though Gareth Bale managed to steer home a late equaliser for Real.
Although Barca had already claimed the title, Sundays Clasico was still a high-intensity, extremely hard-fought affair, with the build-up somewhat tainted by Reals refusal to give a guard of honour.
But Zidane showed plenty of class after the match, waiting for Iniesta in the tunnel after Barcas on-pitch celebrations to congratulate the playmaker.
Speaking about Iniesta before the match, Zidane had given a glowing tribute: As I said in my press conference the other day, he is a player we all admirer.
He is not just any old player in terms of what hes achieved and the person he is. We all know what hes like. So, we just want to congratulate him on his career and wish him luck in the future.
With Real unwilling to give a guard of honour, Gerard Pique rather cheekily got the rest of the Barca squad and staff to conduct one of their own after hanging on to draw against Real on Sunday.
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