Yannick Nézet-Séguin might be expected to end his first season as Philadelphia Orchestra music director with some sort of awesome bang, if only because he's that kind of guy.

Instead, the final program of the Kimmel Center season on Thursday had a "to be continued" quality, with fairly standard repertoire in somewhat unusual configuration, but in performances that showed something extraordinary is underway here.

Though Nézet-Séguin's taste in programming has expanded the orchestra's repertoire with choral works that are often left to organizations that have trouble affording the Kimmel Center, this concert was anchored by the Brahms Violin Concerto with Gil Shaham in top form, but with the conductor generating a synergy one seldom hears in this oft-played piece, even in recordings.

Though Shaham is a mainstream violinist with a classic Dorothy DeLay/Juilliard School pedigree, he seemed seized by the kind of originality that comes from viewing the music through a pre-Wagnerian lens. Phrases don't linger into what comes next, but define themselves individually, as new twists in an ongoing narrative.

Nézet-Séguin veers in that direction, his background in the choral works of Bach putting him in touch with historically informed performance viewpoints.

Yet, what made the performance most unusual was its approach to beauty. Often, you come away from the Philadelphia Orchestra's Brahms muttering purple words like "gorgeous." On Thursday, plenty of surface luster was there, but almost as a side effect from conceptual beauty - the structure, organization, counterpoint, etc.

At times, Shaham was so inside the music that he played too softly to be heard, at least from my first-tier seat. But you had to respect that. He was heeding his own vision of Brahms - not a received one - while Nézet-Séguin behaved more like a supportive opera conductor than a more-competitive concerto accompanist. Often, he delivered phrase readings that I've never heard before, but that, according to the score, were nothing perverse. Even in music as tightly written as Brahms, alternative readings are possible.

The rest of the concert was bits of this and that, starting with a Wolfgang Sawallisch tribute, the second movement of Schumann's Symphony No. 2 that didn't fare well out of context and led to a somewhat incongruous shift to Janacek's Sinfonietta, which rarely fails to thrill with its augmented brass section.

Occasional coordination problems within the brass and the orchestra at large suggested the players were having trouble hearing one another. On the plus side, Janacek's exclamatory string writing did not get in the way of the Philadelphia sound, though the music's idiomatic rough edges were by no means smoothed out. My guess, though, is that Nézet-Séguin has more cogent performances of this episodic work in his future.

In the Leopold Stokowski tradition, some bonbons ended the concert - three of Dvorak's Slavonic Dances, which are miniature concertos for orchestra and always great to hear, even if the first one was given a bit of a bandmaster treatment. Though these Stoky-style programs have been part of an ongoing tribute to the man who made the orchestra what it is, they prove that time has moved on. No real harm done, since it's all great music, just configured strangely.

Mostly, Nézet-Séguin's first season has been stimulating, fun, deep, and exactly what the orchestra needed at this point in time. Not everything worked (the Martha Graham-style aerialist in The Rite of Spring, for one). And Nézet-Séguin's reputation as a conductor of new music would look quite different if two of the season's three commissions had not fallen through when the composers missed their deadlines. Good or bad, new pieces by Oliver Knussen and Osvaldo Golijov would have generated a lot of discussion, with Nézet-Séguin as catalyst.

But, in the big picture, this is one of those heaven-sent appointments, like Michael Tilson Thomas in San Francisco and Esa-Pekka Salonen in Los Angeles. All the strategy in the world can't make a good relationship happen. The Philadelphia musicians talk about the complete lack of tension in both rehearsal and performance and his down-to-business attitude toward music. That could be a recipe for complacency; instead, it's working out as a ticket to expressive freedom.

Contact David Patrick Stearns at dstearns@phillynews.com.