Chad Harbach's The Art of Fielding cross-breeds two genres with limited gene pools, the baseball novel and the campus novel, and comes up with a vigorous hybrid, entertaining and engrossing, though almost absurdly high-minded. There are only a few passages of unrelieved sporting technicality ("Rick O'Shea laced a one-hopper to the Amherst third baseman, who set in motion an easy double play") and even these are supported by the emotional narrative.

The story begins and ends with Mike Schwartz, all-round undergraduate athlete and driven man, and Henry Skrimshander, who can do only two things, namely place his catcher's mitt exactly where the ball will arrive off a player's bat and then throw it with great force and accuracy to where it needs to be. He is a natural genius as a shortstop, possessor of something closer to a superpower than a talent. Henry's profound knack isn't integrated into anything much resembling a personality, so he must learn to function socially and emotionally, and also to deepen his game in areas other than his mysterious gift, his ability to respond to a response almost before it has taken place. All of this Mike Schwartz, unresenting Salieri to this unlikely Mozart of the baseball diamond, makes possible by getting Henry accepted at his own college of Westish in northeastern Wisconsin.

This sort of relationship between young men once attracted no attention by the intensity of its innocence. The feelings it channelled were the ones that powered not just sporting events but armies and empires. Then the Kinsey report was published, and innocence seemed either self-deception or ruse. The buddy movie has never gone away, though recently renamed the bromance, but it can often seem unsure of itself. Even the simplest attitude is mined with contradictions, as when Homer Simpson, unreflecting homophobe, on being informed by tactful Marge that the local antiques dealer prefers the company of men, replies, "Who doesn't?"

One classic way of making it easier to examine non-sexual closeness between men is to include in the story someone who is unambiguously gay (think of Richard Griffiths as Uncle Monty in Withnail and I), reassuringly of a different species. This seems to be happening in The Art of Fielding when a character introduces himself to Henry with the words, "My name's Owen Dunne. I'll be your gay mulatto roommate." Such generically engineered characters are usually solitaries or else in stable relationships, their sexuality safely earthed. That's how it is with Owen, happily involved with Jason, but then the formula mutates and becomes more challenging.

For one thing, Owen tries out for the baseball team and is accepted. His style is fluid, utterly unmacho, but no less effective for that. Then he breaks up with Jason and becomes involved with the college president Guert Affenlight, across a number of boundaries  race, age and previous orientation, since Affenlight has never before had feelings for a man. Indeed he has a grownup daughter, Pella, who arrives back at Westish at about this point in the plot, after the break-up of an impulsive marriage that derailed her academic career.

These four principals in the story are all young, in their early 20s, but each has been supplied with some paradoxical element cutting across mere youth. Mike Schwartz's body is already letting him down, his knees above all, since his athletic versatility brings with it continuous punishment. Henry, aside from his gift, is like a reclusive little old man. Owen's intellectual precocity and self-protective fogeyish manner age him, while Pella's precocious sense of failure gives her the complex attraction of the older woman. Then there's always her father, 60 but very spry, to act not as a shortstop but as a longstop for those readers unable to identify with puppies, however wounded.

Henry the genius shortstop has links with Roy Hobbs in Bernard Malamud's The Natural (Hobbs calls his bat Wonderboy, just as Henry calls his mitt Zero), but The Art of Fielding has deeper affinities with William Maxwell's wonderful novel The Folded Leaf, published in 1945, at about the last possible moment before Kinsey's report made lack of definition seem like evasion. Maxwell's heroes, Spud and Lymie, have feelings for the same woman, just as Mike Schwartz and Henry both become involved with Pella.

The book's references, though, are mainly to Melville. There's some pretext for this, since Guert Affenlight as a young man discovered the transcript of a historically unlikely lecture given at Westish by Melville in 1880 (he went on to write a book on, guess what, "the homosocial and the homoerotic in nineteenth-century American letters"), but a baseball trophy is not a white whale and Mike Schwartz, stern team captain though he is, bears no resemblance to Ahab. Henry's surname, Skrimshander, suggests scrimshaw, the whittling of whale ivory as practised by sailors, and his team-mate Starblind recalls Melville's Starbuck. Harbach is shrewd enough to withhold a reference where it would seem to be compulsory, when Affenlight the Melville scholar is surprised by the quality of the chowder turned out by the college kitchen.

The Art of Fielding seems to set out to destroy, singlehanded if need be, any idea that college sport is an overfunded and culturally narrow distraction from the real business of education. When Owen says to coach Cox, "I trust you don't object to having a gay man on your team," he replies, "The only thing I object to is Schwartz playing football. It's bad for his knees," which can hardly be the whole truth. There's a Mormon on the team, too, but he seems equally accepting. Crowds at ball games seem to find nothing funny about a player named Quentin Quisp (conceivably Harbach's homage to Queequeg). To paraphrase a remark made at one point by the chairperson of the Committee for Student Affairs, I know Westish is supposed to be a liberal arts college, but can it really be that liberal?

There are so many references to high culture that college baseball comes to resemble some sort of offshoot of Mensa. Mike Schwartz quotes Schiller in a pre-game pep talk. Owen reads Kierkegaard in the dugout. Introduced to Pella, Schwartz correctly identifies her name as that of a city sacked by the Romans in 168BC. Even Henry's point of view dwells on Homer rather than Homer Simpson. All of this would be laughable if it was done with less conviction.

On the book's first page there's an elementary slip in the point of view, with a reference to Mike Schwartz letting "his huge aching back" relax against a chain-link fence. Any creative-writing instructor would point out that Mike may feel the ache but hardly the hugeness, which is information aimed squarely at the reader. Perhaps Harbach has let it stand with the affectionate confidence of a driver who decides, after passing his test, not to respray the scratch in the coachwork that happened the first time he took the wheel.

Chad Harbach's debut novel of baseball, friendship and late-flowering love has been a great success in America. Enthusiastically plugged by everyone from Jonathan Franzen to James Patterson, John Irving to Téa Obreht, praised to the skies by the New Yorker, GQ, the Oprah Magazine and the Milwaukee Sunday Journal-Sentinel alike, it was also chosen by the New York Times as one of the 10 best books of 2011. In October, Harbach's friend Keith Gessen, author of All the Sad Young Literary Men, gave the publicity campaign a mighty push by publishing a long article in Vanity Fair, now an ebook, which told the stirring story of the book's genesis: Harbach, a quiet, unassuming young literary man from Racine, Wisconsin, had toiled away on the novel for 10 years, while doing the Brooklyn equivalent of starving in a garret  working on a small literary magazine and supporting himself as a copywriter while fending off the debt collection agencies. Then, in late 2009, after endless setbacks and rejections, a young agent took on the book, and a bidding war ensued, with Little, Brown stumping up an advance of $665,000. It has been riding high in the US bestseller charts.

It's easy to see why The Art of Fielding has done so well: it is charming, warm-hearted, addictive, and very hard to dislike. The story begins at an amateur baseball tournament in Peoria, Illinois, where Mike Schwartz, an outsized college athlete, notices "a scrawny novelty of a shortstop"  the shortstop is a crucial fielding position, right in the firing line of right-handed batsmen  fielding practice balls with an almost superhuman grace. He is Henry Skrimshander, the shortest member of an undistinguished team of South Dakota farm boys. Schwartz, a budding baseball Svengali, immediately discerns a "transcendent talent" and decides to bag him for his university, Westish, an idyllic if slightly inglorious (fictional) liberal arts college on the shores of Lake Michigan in Wisconsin. Under Schwartz's tutelage, Henry bears out his promise, galvanising the baseball team, the Westish Harpooners, into its best results in living memory, and personally chalking up the longest streak of error-free games since the great Aparicio Rodriguez (also fictional), the author of a quasi-philosophical tome called The Art of Fielding (sample quote: "Death is the sanction of all that the athlete does").

Henry is on the point of being snapped up by a major league team for a six-figure sum when he falls victim to a sudden, inexplicable and total loss of form. This is heralded in a setpiece scene in which one of Henry's throws goes violently awry, with crucial consequences for the other main plotline: the college president Guert Affenlight, a Herman Melville scholar, realises that after a lifetime as a light-hearted heterosexual shagger, he has fallen desperately in love with Henry's teammate Owen. Meanwhile, Affenlight's daughter Pella has decided to come to Westish in order to escape an unhappy starter marriage with an older man, and falls for Schwartz. All of this happens quite fast, in the first 80 pages; the rest of the book untangles the ramifications.

The Art of Fielding feels like a novel from another, more innocent age. It revels in themes that have been unfashionable in literary fiction for generations  team spirit, male friendship, making the best of one's talents. In its optimism and lack of cynicism, in its celebration of the wide open spaces of the Midwest and its confidence in the deep inner meaning of baseball, it is a big American novel of the old school. Both Schwartz, the self-made man from south central Chicago, and Henry, the super-talented son of a metalworker from Nowheresville, South Dakota, are embodiments of the American dream, just as the Harpooners, a harmonious whole made up of prep school boys, Jews, Asians, Latinos and African Americans, is an idealistic microcosm of the republic. The great thing is that, by and large, the book makes all these potentially hokey themes convincing, even to decadent Europeans with no knowledge of baseball. The sporting detail poses some incidental problems ("Cut two, cut three, cut four, third to first, first to third, 5-4-3, 6-4-3, 4-6-3, 1-6-3, 3-6-1, charge bunt, charge bunt, charge bunt," runs one heroically impenetrable line) but is mostly easy enough to follow.

According to Gessen's article, the story began as a postmodern tale in the vein of David Foster Wallace's Infinite Jest  hence, presumably, the outlandish central conceit, and the long, silly names  and later re-emerged in a much simpler style, looking dangerously like a Disney film. The final version is somewhere in between the two, comparable to a US indie film: an old story originally told, heartfelt but offbeat, with sharp dialogue, likeable protagonists and amusing minor characters.

The plot perhaps cleaves too closely to the generic conventions of the team sports movie, right down to the climactic scene where everything depends on one moment's play. And the characters tend towards the wish-fulfilment end of the spectrum: the heroic mentor, the quirky, brilliant friend (Owen introduces himself with the surprising words "I'll be your gay mulatto roommate"). The prose occasionally descends into tired journalese or bog-standard sports filler: "Rick had saved his butt. They were ahead 2 to 0 " But in general the effect is pretty much irresistible. Harbach's writing has been frequently compared to Franzen's, and shares an intelligent, unaffected directness. The Art of Fielding also has a similar post-postmodern, post-ironic appeal to Franzen's novels: it creates a richly peopled world that you can fully inhabit in your mind, and to which you long to return when you put it down.