He did not look capable of holding, much less playing, his tenor saxophone during a weeklong recording session scheduled for him. One of jazz’s most influential tenor saxophonists over the last quarter-century and an 11-time Grammy winner, he had been battling myelodysplastic syndrome, a bone marrow disease commonly known as MDS, for more than a year and would pass away about four months later, at 57.

But he did hold his saxophone, and played it extremely well, for the grueling weeklong session that would result in his final recording, “Pilgrimage” (Heads Up), a collection of nine originals, released last week. Among the selections is “When Can I Kiss You Again?,” a ballad whose title comes from a question that Mr. Brecker’s son, Sam, asked him during a hospital visit when physical contact with his father was prohibited to prevent infection. And the CD’s final track is the 10-minute “Pilgrimage,” a song that alternates between serene ensemble playing and tumultuous soloing from Mr. Brecker.

“In its balance of ambition and abandon, serious-mindedness and ebullience,” Nate Chinen wrote of the new album in The New York Times, “there’s a crystallization of what jazz, at its best, is all about.”

Mr. Brecker’s favorite collaborators — the guitarist Pat Metheny, the bassist John Patitucci, the drummer Jack DeJohnette and the pianists Herbie Hancock and Brad Mehldau — all agreed to attend the session on short notice. Mr. Brecker had played on more than 900 albums, including familiar pop solos on Paul Simon and James Taylor tunes, but now it was apparent that his days were numbered. A reporter was invited to document a day of recording.

Not that there was anything morbid about Mr. Brecker. He became energized immediately upon reuniting with his longtime sidemen. He cast off his cane and began zipping around the studio taking care of logistics.

“Even the first day in the studio, we didn’t know if the whole thing was going to happen,” said Mr. Brecker’s manager, Darryl Pitt. “But Mike just kept getting stronger and stronger in spirit, and it carried through him physically.”

The band clicked immediately. During preparations, Mr. Metheny began running quick arpeggios, which Mr. Patitucci mimicked on bass. Mr. Brecker followed suit on saxophone, and Mr. DeJohnette began singing along. Mr. Hancock, meanwhile, set up a Fender Rhodes electric keyboard next to a grand piano and began playing each with one hand.

“You’re doubling, Herbie,” Mr. Brecker said.

“Yeah,” Mr. Hancock replied jokingly. “I get double pay.”

Mr. Hancock winced as he struggled to finger some of the chord voicings Mr. Brecker had written for the piano part.

“That’s some serious stuff right there,” he declared, prompting the other musicians to cheer Mr. Brecker.

“Iron Mike,” Mr. Patitucci yelled, a good assessment of Mr. Brecker’s surprising strength and endurance that week. In a phone interview after the recording session, Mr. Brecker said, “I must have been running on adrenaline, because I collapsed after it was over.”

Mr. Brecker had stopped performing publicly in 2005 and was often too weak to practice his saxophone. Still, he displayed during the sessions the trademarks of his playing: distinct tone and daring harmonic forays. His performance seemed to reflect the urgency of his situation. His lines were probing but purposeful. He reared his body up and down with emotion as he played, and often grunted midphrase.

“His whole life — all the life he had left — was pouring out of his horn,” Mr. Pitt said. “There was nothing left in him after the session.”

“Michael was extremely self-critical and hardly ever felt that he played well,” he added. “This was the first time I’ve heard him — in his career — say he was satisfied with what he’d done.”

Mr. Brecker was so ill that he often composed music in bed, using a portable keyboard, his electronic saxophone and his laptop.

Yet Mr. Hancock, who has recorded and performed with him since the 1980s, said: “Michael has gone up yet another notch with his writing and playing. He’s taken something that’s destructive and turned it into something extremely constructive.”

Mr. Metheny, who appeared on Mr. Becker’s first solo album, in the late ’80s, said, “There’s no one else who would or could write anything like this.”

Mr. Brecker said that in a way, his illness helped his creative expression by giving him a sense of “extra purpose” and a new feeling of freedom as a composer.

Mr. Pitt said Mr. Brecker did not want the other musicians to know the pain and discomfort he was in during the session. During the months that followed it, Mr. Brecker became obsessed with adding tracks and remixing the album, he said.

“Making that album kept Michael alive,” Mr. Pitt said. Shortly after he pronounced the recording finished, Mr. Brecker died.