Despite the happy talk of some critics, improvisation in classical music is a lost art. In the 18th and 19th centuries, however, composers were frequently asked to play extemporaneously, often to great effect. One heralded evening, Anton Bruckner sat at the organ and interwove themes from his new Symphony No. 8 with those of Siegfried’s Funeral Music from Richard Wagner’s “Götterdämmerung,” in what, by all accounts, must have been a glorious and inspiring manner.

The Nowak version of the Eighth Symphony from the 1950s that Lorin Maazel chose for the New York Philharmonic’s last concert of his penultimate season would have sounded like improvisatory material to Bruckner. Almost all of his 11 symphonies — there are nine in numerical sequence, a student symphony, and one with the “Alice in Wonderland” designation of “symphony number zero” — went under the knife of the editors, but none was so radically changed as the eighth.

Mr. Maazel hears a certain sound in Bruckner — craggy, impassioned. Quite appropriately for a composer who dug down deeply into the religious tradition of rural Upper Austria, this performance reminded of a medieval woodcut: rough-hewn edges and a two-dimensional perspective. In the main, the Philharmonic executed well. This had been Mr. Maazel’s audition piece when he vied for the orchestra’s music directorship once it was announced that Kurt Masur was being jettisoned. At that time, the ensemble offered this particular Bruckner sloppily and with poor intonation. Mr. Maazel got the job anyway — beating out, if you can believe it, Mariss Jansons. On Saturday evening, we finally heard what Mr. Maazel wanted in the first place.

The Allegro moderato was exciting if a bit harsh. There may be a chicken-and-egg situation here: Did the orchestra project brittle, sometimes bordering on ugly, because maestro wanted to live on the edge, or is this pushing-the-envelope approach the child of the unfortunate quotidian sound of the Philharmonic’s violins?

The Scherzo was powerful but restrained. Rhythmic intensity was sometimes implied rather than emphasized, the timpani held in check rather than driving this propulsive effort. Brass accents were precise and notably clean.

The great Adagio, once described to me as the aural representation of the building of a Gothic cathedral, saw the beginning of a rather unfortunate raveling of musicianship. On the plus side, Mr. Maazel got us all out of there by 9:30, but his quick tempos throughout sometimes swept away Bruckner’s more poetic statements. Our esteemed director painted himself into a corner somewhat early on. The movement, like the Adagio in Mahler’s Third, is essentially one giant half-hour crescendo. Maestro moved into loud territory much too quickly and then had nowhere to go but triple forte. By the end of the movement there was a noticeable din that subsumed some of the more delicate passages, particularly the crucial harp figures that accentuate the paradisiacal geography of this celebrated movement. The two women might just as well have been miming their parts. A noticeable number of patrons left the hall at the movement’s conclusion.

Up to this point, the brass section, including a full complement of Wagner tubas, had had a great night. But Bruckner is a notorious lip-killer and the Finale saw some gaffes, particularly in the trumpets. Again the group was too loud, drowning the vital and eloquent horn passages at the work’s conclusion. But overall this was fine music-making, the conductor adding a little frisson to his color scheme and finally allowing the lone percussionist to let loose. If this performance did not capture every detail of this Brobdingnagian landscape perfectly, it certainly projected the overriding spirit of an ecstatic man of faith painting a charismatic portrait of the universe his God created.

So the season ends and Mr. Maazel has one more year to balance the books on his legacy. But vacation is short, as the Phil is a 52-week orchestra, so summer begins tomorrow in Central Park.