There are still major conductors — some among the most passionate champions of Gustav Mahler’s music — who refuse to perform any version of the composer’s unfinished Tenth Symphony.

For those at Macky Auditorium on Saturday evening to hear it presented by the Colorado MahlerFest Orchestra, such purist sentiment must ring incredibly hollow.

Maestro Kenneth Woods — in his second year as music director for the venerable Boulder festival, which is now held every year in late May — made such an impact with his interpretation of the work that this could be pointed to as the moment where he truly took up the mantle of former director Robert Olson, who founded MahlerFest 30 years ago.

For the first time, MahlerFest performed the performing version by Deryck Cooke — the earliest and by far the most well-known of the various full realizations of the symphony. Woods demonstrated a profound familiarity with the Cooke score, and was reverential to the English musicologist’s vision — that this is Mahler’s music, and Cooke was only a medium through which it could be heard.

The first movement — which Mahler basically finished orchestrating — is easily the most familiar part of the Tenth. Woods showed intense focus in shaping the profound 24-minute movement.

Its shattering, dissonant climax arrived with walloping force, yet the peaceful, beautiful coda — which Mahler extended to an almost unbearable level — emerged out of the climax in a natural, wholly organic way.

Where Woods and the MahlerFest musicians were most impressive, however, was in the second movement. A jubilant and rambunctious affair, this scherzo-type piece must surely be the most difficult Mahler ever wrote — and it is more challenging than many better-known 20th-century virtuoso orchestral works.

Its constantly shifting meters, played at a dangerously fast pace, were a tour de force for the musicians of the orchestra. For a group of people who only come together once a year for this purpose, it was an amazing feat of brilliance.

The final three movements (which are thematically related) did not disappoint, especially the huge finale. In the slow introduction to that movement, Kay Lloyd’s flute solo was otherworldly. Woods had a unique take on the famous repeated strokes from a muffled drum that characterize the movement’s opening. Rather than have them blasted out like cannon fire — as is heard on many recordings — Woods placed the drum offstage and went for an authoritative, but not earth-shattering sound.

At the festival symposium during the day Saturday, Woods explained this approach paid homage to Mahler’s supposed inspiration for the drum strokes — a funeral procession for a New York fireman he heard outside his window.

Like the first movement, the finale closes with a greatly extended slow coda, which Woods took to ethereal heights.

Cooke died in 1976, shortly after publication of his performing edition. One of the musicians who assisted him in the work, composer David Matthews, was on hand for Saturday’s performance at Macky. Woods opened the concert with the American premiere of an arrangement for string orchestra by Matthews of the String Quartet by English composer Edward Elgar, one of that composer’s final works.

It was a good choice for several reasons. Being written for strings alone, it allowed the wind players to conserve their energy for the demands of the Tenth. It was a fine display of Matthews’ skill as an arranger, and a fitting tribute for a distinguished guest who played such a large role in the preparation of Cooke’s edition. Matthews himself delivered a beautiful and moving talk at the symposium, paying a heartfelt tribute to Cooke and giving a solid explanation of both the methods used and the justification for preparing a performing version of the Tenth.

With the convincing performance of the Cooke Tenth, Woods filled one of the few holes on MahlerFest’s “bucket list.” The concert is repeated 3:30 p.m. today at Macky. Tickets are available at the door or online.

It was announced that the major work for next year’s MahlerFest XXXI will be the orchestral song cycle “Das Lied von der Erde” (“The Song of the Earth”). That piece — written between the Eighth and Ninth Symphonies and often counted among the symphonies (making a total of 11) — was last performed at Macky in 2007 with world-famous baritone Thomas Hampson.