When big-name soloists venture into the conducting arena, there’s often a sense of cautiousness about the endeavor. You frequently see soloists conducting from the keyboard or with violin in hand, joining a long tradition but not quite freeing themselves from their instrumental origins. Nikolaj Znaider, however, is one who has plunged in at the deep end. Having performed the Brahms Violin Concerto as soloist with the National Symphony Orchestra last week, he is giving the second program of his two-week NSO mini-residency on the podium, conducting not a violin work but Mahler’s First Symphony — without an instrument, or even a score, thank you very much.

Znaider gave a thoroughly accomplished performance Thursday night. Yet for all of his smooth, easy motions and urbane presence, tall and athletic at the head of the orchestra, there was some vestige of caution, in that the whole thing didn’t feel very risky. That’s hardly surprising: Even more than conductors, soloists are held to near-impossible standards of technical perfection. What that translated into in Znaider’s case was a very polished performance that risked, at times, becoming a bit monochromatic in its urbanity.

This, certainly, was true of the first piece on the program, ­Mozart’s final piano concerto, K. 595 in B-flat major. Znaider’s approach to Mozart is old-school: rich, round and robust. Throughout the evening, he found a way to a kind of lush lustre in the orchestra that is one of its best attitudes. But with all of that polish, the piece lost some of its drive, the excitement of a raw edge. It certainly wasn’t the kind of light, lithe Mozart colored by historically informed performance practice, though that’s not to say Znaider is unaware of the same.

The soloist was Benjamin Grosvenor, who, having made his debut with the orchestra at Wolf Trap a couple of summers back, returned — now far better known — to make his first appearance with them in the concert hall. Grosvenor’s sound and Znaider’s approach were a good fit: Grosvenor, too, plays with a round fullness. He started out with an attempt at force that caused a couple of little bumbles, but neither the force nor the tiny slips were enough to bring him out of the elegant poise he offered, attractive, but not, in this performance, always wildly compelling. Overall, it was a performance very pretty in many details but somehow uninvolving.

Time was when a concerto was the audience favorite on a program. Thursday, though, the evening’s real tension focused on the Mahler — and the Mahler was also the evening’s payoff. Znaider adroitly avoided emotional cliche — not necessarily an easy thing to do with a composer who offers so much temptation and precedent for heart-on-the-sleeve antics — and afforded fascinating glimpses into the conductor he is in the process of becoming. Most welcome was that he offered a Mahler that was thoughtful but without too much pathos from the very beginning, when the quiet opening chords were thoughtfully sustained but not melodramatic and the horn calls that punctuated them had a kind of burbling lightness rather than a sense of portent.

Znaider’s performance of the Mahler had some of the same traits as his Mozart. An approach that sounded a little large and romantic in Mozart became slightly small-scale and intimate in the Mahler, in part because it didn’t aim at the kind of all-caps telegraphing of major emotion to which so many conductors aspire with Mahler. The restraint proved welcome here; while the first movement had moments of dragging, for the most part Znaider kept the music moving along lightly, with a sense of buoyancy and a lurking smile that isn’t always present in this work, at least not quite so subtly. The third movement was rollicking but not stereotypically rustic, and the fourth opened with a blast of intensity yet retained a sense of intimacy.

Mahler performances can fall victim to grandiloquence. Znaider kept his rhetorically varied and on a human scale, so you sensed that it was the statement of one person rather than the opening of the beyond. It was refreshing and approachable, and the audience loved it, an impressive sign for a conductor still proving to the world, and to himself, that he’s more than just a pretty violinist.

The program repeats Saturday night at 8.