Imag­ine, if you will, tak­ing a seat at the piano before a full house of 2,000 music lovers ready to hear Mozart’s Piano Con­cer­to No. 20 in D minor — and, more impor­tant­ly, on stage with an orches­tra and con­duc­tor more than ready to play it. That would be dif­fi­cult enough, but now imag­ine that you thought you were sup­posed to play the Piano Con­cer­to No.23 in A major, anoth­er piece of music entire­ly. This is the stuff of night­mares, and indeed, the very sit­u­a­tion in which pianist Maria João Pires found her­self in 2013, after she’d been recruit­ed to fill in for anoth­er play­er at an open rehearsal held at Ams­ter­dam’s Con­cert­ge­bouw. You can watch it unfold, assum­ing you can bear it, in the clip above. As Pires says in the Clas­sic FM inter­view below, it had been “per­haps 11 months” since she’d last played the piece into which she could hear the orches­tra launch­ing, “and that’s the moment where you start los­ing the mem­o­ry of the details. That’s how the mem­o­ry func­tions, you …