Sergio Rigon was born in Vercelli, in Italy's Piedmont region, in 1934. He came up through the Jazz Club Vercelli, founded in the city in 1953, as one of the circle of young local players the club produced, and Discogs's own artist note calls him simply "Italian jazz saxophonist and clarinetist from Vercelli (1934-2014)." A 2017 history of Vercelli's jazz scene, published by Infovercelli24, credits him as the first Vercelli native to appear on a contemporary jazz record and says he came to be regarded as perhaps the finest baritone saxophonist Italy produced, as well as an accomplished flautist; his hometown later remembered him as the "re del sax baritono," the king of the baritone sax.

He spent his working life split between Italy's broadcast and session world and its jazz scene. He played in RAI's "Ritmica" radio orchestra, in Armando Trovajoli's orchestra, and in the house orchestras that backed the Sanremo Festival; the most-told story of that side of his career is his place in the orchestra that accompanied Wilson Pickett's performance of "Deborah" at Sanremo in 1968. Discogs documents the same studio career at length: he recorded repeatedly with Mina between 1968 and 2018, played on Toto Cutugno's Innamorata, Innamorato, Innamorati (1980), on records by Rettore and Pierangelo Bertoli, on the Italian soundtrack release of Carmine Coppola's Il Padrino Parte II (1975, the Italian edition of the Godfather Part II score) alongside fellow saxophonist Giancarlo Barigozzi and bassist Giorgio Azzolini, and on flute on three Astor Piazzolla tango releases cut in Italy between 1977 and 1992 (Mundial 78, Carosello Italiano 1974-1984 Vol. 4 - Tango Blues and Tango Forever), again with Azzolini on bass. An easy-listening album of South American standards, Successi Sudamericani (PDI), credits him under the name variant "S. Rigoni," playing alto saxophone in an orchestra arranged and conducted by Achille Ovale.

Alongside that session work, Rigon was a working member of Italy's leading postwar jazz big bands. Discogs-verified session credits place him on baritone saxophone in Giorgio Gaslini's big band on three recordings: Il Fiume Furore (I Dischi Del Sole, 1968), a live recording of a political theater-and-jazz work for the Nuovo Canzoniere Italiano, taped at Milan's Teatro Lirico and Centro Culturale De Amicis; Grido (Durium, 1968), also live, on which the reed section includes the American soprano saxophonist Steve Lacy alongside Gaslini on piano; and Newport In Milan (OFF/Produttori Associati, 1971), a big-band session that also carries Eraldo Volonté, Gianni Basso, Glauco Masetti, Dino Piana and Oscar Valdambrini. A 2024 local retrospective of Vercelli's jazz history describes this side of his career as "free and avant-garde" recording with Gaslini, set against his more traditional, dixieland-rooted work accompanying the American violinist Joe Venuti on his Italian tours.

Rigon was also a member of Giorgio Azzolini's fourteen-piece Giorgio Azzolini Big Band (Dire, recorded in Milan in 1971), on baritone saxophone and flute, alongside Franco D'Andrea, Gianni Bedori, Giancarlo Barigozzi, Emilio Soana and the Swiss drummer Pierre Favre; one of its tracks, "Blues Deflection," was later anthologized on the compilation Il Jazz In Italia II (Fabbri Editori, 1981). He was a recurring member of Gil Cuppini's big band as well, on the live recording Sof 'Stroke (Meazzi, recorded at the Universal Club in Marina di Carrara in the summer of 1968, with Dusko Goykovich featured on trumpet) and on the sessions later anthologized as Gil Cuppini Groups & Big Band (Ducale Jazz, 1984), Caprice (Musica Jazz, 1997) and the Japanese CD reissue A New Day (Sound Hills Records, 1997); the same Cuppini orchestra backed Joe Venuti on the violinist's first Italian concert tour, documented on Welcome Joe! (Durium, 1974, on alto saxophone) and The Incredible Joe Venuti (Audiophile, 1977, recorded in 1971, on tenor and alto saxophone). He also plays baritone saxophone on three tracks of Henghel Gualdi's Now (Cap Studio, Milan, 1976) and is one of the horns, with Gualdi, Ettore Righello and Emilio Soana, on "Stella By Starlight" on the compilation Il Meglio Del Jazz From Italy (Carosello, 1977).

His most internationally pointed jazz credit is Jazz A Confronto 18 (Horo Records, recorded in Rome on January 25, 1972, released 1975), billed to the Summit Big Band and led by the American trombonist Slide Hampton and the Yugoslav-American trumpeter Dusko Gojkovic: Rigon plays baritone saxophone in a band that also carries the American tenor saxophonist Sal Nistico, trumpeter Benny Bailey, bassist Patrice Caratini and pianist Vince Benedetti alongside Gianni Basso on tenor saxophone.

His only record as a leader, Feelings (Red Record, recorded at Barigozzi Studio in Milan in November 1980), is a quartet date with Ettore Righello on piano and electric piano, Carlo Milano on bass and Giampiero Prina on drums. Rigon plays baritone saxophone, flute and bass clarinet across five originals ("Deal," "Rubia" and "Flint" among them) and a set of standards - "Secret Love," "Lush Life," Sonny Rollins's "Tenor Madness," "You Stepped Out Of A Dream" and "The Nearness Of You." It has never been reissued on CD. A Vercelli retrospective on the city's jazz recordings credits Rigon as the first Vercelli-born musician to appear on a contemporary jazz LP under his own name, and separately notes that he was one of the few Italian musicians included in the 103-volume series "I Grandi Del Jazz" (The Great Jazz Masters), published by Fratelli Fabbri Editori in 1979, playing flute on its Joe Venuti volume.

Rigon died in May 2014, at the age of 79. A memorial concert, "Forever Sergio Rigon Octet," organized by the drummer Claudio Saveriano, was staged in Vercelli in 2018 in his memory. A local obituary notes that his brother, Renzo Rigon, was also a saxophonist, playing alto sax.

Rigon's catalog splits between two worlds. Of the roughly fifty releases Discogs credits to him, thirty-one carry the Jazz genre tag, among them his own leader date and his work in the big bands of Gaslini, Cuppini and Azzolini, which Discogs variously tags Free Jazz, Big Band, Cool Jazz, Post-Bop, Contemporary Jazz and Dixieland. The other half of the catalog is the working Italian studio musician's life: Sanremo Festival and RAI orchestra dates, pop sessions with Mina, Toto Cutugno, Rettore and Pierangelo Bertoli, a film soundtrack (Carmine Coppola's Il Padrino Parte II) and Astor Piazzolla's Italian tango dates. Feelings, his one album as a leader, sits in the bebop-and-standards tradition - a program built on jazz songbook staples rather than original material alone - while his work for Gaslini's big band, which put him in a reed section alongside the American free-jazz soprano saxophonist Steve Lacy, represents the free and avant-garde end of his output. His work with the Summit Big Band under Slide Hampton and Dusko Gojkovic on Horo Records, playing beside American sidemen Sal Nistico and Benny Bailey, is the most internationally oriented hard-bop credit in his discography. He is remembered in his hometown specifically as a baritone saxophone specialist, a comparatively rare lead voice in Italian big-band jazz of his generation.