In her first Celebrity Series and Jordan Hall appearance this past Sunday, violinist Lisa Batiashvili joined pianist Paul Lewis, whose recitals for the Celebrity Series and concerti with the BSO have taken Boston by storm. Both young, but with reputations exploding, these remarkable artists filled an afternoon with bravura, much splendid music making, and a terrific example of today’s salutary violin recital transformation: fiddlers choosing to pair with pianists who are at least their equal.

The program was carefully designed to demonstrate parity, starting with a Schubert sonata in which the voices are about equally prominent, followed by a Schubert showpiece, primarily for the violin. After intermission came brief solo turns for each, and then to complete the symmetry, Beethoven’s final sonata in G major (Op.96) carefully labeled “for piano and violin.”

As a 19-year-old, Schubert wrote three short sonatas for violin and piano, and then a year later the one we heard, a more extensive work in A major (D574), dubbed the “Grand Duo” by his publisher who must have had a marketing degree, because the first three ended up as “sonatinas,” thereby relegated to a subsidiary role, although to me they are far more delicate and lyrical and indeed presage some of Schubert’s greatest works. The Grand Duo is not easy to render coherent and convincing. Relatively short lyrical moments contrast with stormy, brilliant show-off passages, and as is sometimes Schubert’s wont, the first movement in particular has a lot of patches without quite making it to a full quilt. Next comes a Scherzo, marked presto, but played as fast as humanly possible on Sunday. Then there’s an andantino that’s both charming and perhaps the high point of the work. Finally there’s a “rousing” finale in which the players play rapid arpeggios, staccato chords, and generally race over their instruments.

Nine years later, in 1826, Schubert wrote a Rondo in B Minor (D. 895) for the violin, now clearly with piano accompaniment. At that point he knew a brilliant young Czech violinist, Josef Slavík (Slawjk), who was apparently viewed as a competitor to Paganini. Schubert pushed his friend hard, and the work earned the epithet, “Rondeau Brilliant,” but I think that’s a pity. It’s actually a fine example of Schubert’s extraordinary lyricism, and while much of it is indeed “brilliant,” it holds together better than the Grand Duo.

In performing these works, differences in the basic impulses of the two performers became apparent quickly, and overall the differences added to my enjoyment. Lewis shows the influence of Brendel, his principal mentor. While there’s plenty of passion and excitement, his playing is first and foremost governed by a finely-tuned, delicate, but determinedly steady rhythmic impulse. He’s not afraid of moving around within the bar lines, but he always magically seems to come out just right. Batiashvili, on the other hand, puts romanticism and passion first. She luxuriates justifiably in her extraordinary finger velocity, her ease, her lovely sound and technical mastery. But even though her partner comes across as more controlled, more considered, more “classical,” the ensemble was invariably first rate.

After intermission, the program was not as advertised. The duo were to play one of Bach’s sonatas (BWV 1023) in which Lewis would have had to accompany with a continuo that Bach left unrealized, and I could hardly wait to see what he would do with that. But I’m still waiting; he played instead Busoni’s transcription of Bach’s Chorale Prelude, “Nun komm’ der Heiden Heiland,” (BWV 659). I didn’t catch the name from the rapid announcement of program change prior to the concert, but the pianist seated next to me leaned over and whispered, “That must be a Busoni transcription.” She was right, and it was marvelous, albeit all too brief. Lewis recreated an organ with several warm but always separate voices. I wouldn’t have expected it from Lewis; it brought to mind Murray Perahia, with his amazing ability to turn a piano into several different pianos. And along with the voicing came calm, rhythmic suppleness, and gorgeous sound. Terrific. Perhaps the high point of the concert.

Batiashvili then took a brief and spectacular turn, playing Telemann’s Fantasie No. 4 for Solo Violin in D Major TWV 40:17. Written in 1735 while Bach was very much alive. Influenced by Corelli and perhaps Bach, Telemann wrote some solo violin works that deserve more recognition, and Batiashvili proved an important tutor for those in the audience unfamiliar with them. Light-hearted, scintillating, ferociously demanding with double, triple stops and quadruple stops designed to fly by, the work may not be deeply memorable, but if a fiddler wants to demonstrate command of her instrument, they are perfect. And Batiashvili has extraordinary control, both of her bow arm and of her left hand. Violinists in the audience had to be shaking their heads while she was just plain having fun. There was a spontaneous roar at the end of this dazzling miniature.

Beethoven’s last of ten sonatas for “piano and violin” was composed when he was leaving his “middle period” on the way to the “late” piano sonatas and string quartets. It forms thereby a musical bridge, but it was also written for the Archduke Rudolph and premiered by Pierre Rode, the eminent French violin virtuoso who had recently arrived in Vienna. It includes a virtuoso passage that appears rather suddenly in the fourth movement, quite likely inserted to help the newly arrived violinist show off. On this occasion, the speed and virtuosity that Batiashvili and Lewis demonstrated toward the end of the last movement might well have left Rode short of breath. Nevertheless, when it comes to playing all the notes, it may be the easiest of his sonatas technically, and Lockwood sums it up perfectly as a “reflective, lyrical and subtle” work.

The performance was fine, but it could have been better. Lewis was spectacular. He played to balance his partner and stayed away from undue volume. The lid was fully open, and in passages marked fortissimo he held back. But there were many gradations, and the playing was truly noble, with subtle dynamic and rhythmic variations. As an example, the opening of the slow movement, an extended introduction by the pianist, was gorgeous: calm, elegant, straightforward, but with a barely perceptible rise and fall in the long line that introduces the violinist. Batiashvili also showed how musical and sensitive she can be. Her sound is unfailingly both clear and warm; she is always attentive to her partner. In the slow movement, in particular, she too glowed.

What was missing for me? A strange combination: meticulous attention to Beethoven’s markings, along with a truly creative impulse. I recall Menachem Pressler in a master class berating a highly talented young pianist for not paying obsessive attention to Beethoven’s markings, and yet who has brought more life and imagination to Beethoven than Pressler? In Sunday’s performance, two retards in an important transition in the first movement were virtually absent, Batiashvili only hinted at many of the sforzandi, and tempi in the last movement seemed unsettled and at times arbitrary. Moreover, differences between the two artists seemed here to get in the way. The very first notes setting the stage started with a rapid trill by the violinist, followed by a more leisurely one by the pianist.

At the end there was a roar, rather than silence followed by growing applause. That’s not the way this tentative, introspective, and rhapsodic sonata should be received. I reviewed a performance by the very young violinist, Benjamin Beilman, and the venerable pianist, Gilbert Kalish, at the Gardner last fall. There wasn’t the brilliance, the in-your-face romanticism. Instead there was lyricism, languor, fluidity, and many surprises. I think it will stick with me longer [my review is here].

Two encores followed: A virtuosic rendering of one of the Brahms/Joachim Hungarian dances, and Kreisler’s Liebesleid (which I missed, but I’ll bet it was ravishing).

Batiashvili’s concerto performances earn justified and invariable raves, but I don’t believe she’s had many extended tours as a recitalist with piano. After several concerts with this program around the world, the ensemble is first rate, but both freedom and unanimity of musical impulse remain elusive. Listen to Arrau and Szigeti, Faust and Melnikov, or Kremer and Argerich playing the last Beethoven sonata, and I think you’ll hear what I’m referring to, even though each of those duos could not be more different, one from another. But what a future this duo could have. They have all the makings. They just need a bit more time.

And one more thing might help: A better violin. On this afternoon, from where I sat, two thirds back in the orchestra, a bit left of center, in front of the balcony overhang, the Guarneri del Gesu that Batiashvili has been lent sounded thin, lacked sparkle, and had little character. The result was that while Lewis was remarkable in controlling his piano to accent clarity and transparency, the violin didn’t cut through sufficiently to balance the voices. You heard it, but it didn’t ring. A great del Gesu of this latish period of his short career (1739) often has a low end that sounds like an organ, and overall a combination of smoke and fire that sounds ridiculous when I write about it, but will win rapid attestation from most violinists lucky enough to play on such instruments. There are three possibilities; 1) the violin was out of sorts (by far the most likely). It’s been on the road, winter dryness is yielding to humidity, etc. Violins can be moody, just like everyone else. 2) It’s not one of the great del Gesu violins. That would be a shame, because a quick trip to YouTube demonstrates how extraordinary Batiashvili can be playing a great Strad, as she did until recently, or 3) To complete the possibilities in an unpleasant way: It’s not a del Gesu; Because of his spectacularly free, rough and ready craftsmanship, particularly toward the end of his life, no violinmaker has been copied more often, and there have been friendships ended, claims and counter claims, lawsuits, and probably duels between those who claim a del Gesu to be the “real thing,” versus one of the devilishly skillful copies that British, French and Bohemian makers have long crafted.

What’s highly likely is that the lack of an extraordinary sound wasn’t Batiashvili’s fault. She’s an amazing violinist. Perhaps she could play more slowly on occasion; perhaps she should study a score more avidly; perhaps she could vary her vibrato and sound a bit more, perhaps, perhaps…but she’s very special, and I urge all readers not to miss her next time she’s near by. And as for Lewis? For me, he’s the cat’s meow.

Tom Delbanco is the Koplow-Tullis Professor of General Medicine and Primary Care at Harvard Medical School and Beth Israel Deaconess Hospital. An avid violinist since age nine, he has particular interest in the evolution of stringed instruments from the 16^th century on.