They begin with Puccini – a passionate Rodolfo and a quicktempered Marcello – and end with a chilling Otello, Tézier’s Iago dripping poison into Kaufmann’s ear in the Act II duet, with Antonio Pappano throwing up a terrifying barrage of sound with the Orchestra dell’Accademia Nazionale di Santa Cecilia.

[Otello Act II Duet] In vocal terms Tézier keeps up his end, although Kaufmann soars beyond him. In the most important ways Tézier’s Iago rises to the dramatic occasion. This duet and the three from La forza are the highlights of the disc. They bring out the singer’s [Kaufmann's] not inconsiderable vocal gifts and a fair measure of musical expression. As a Verdi tenor he remains non pareil.

Neither is Italian, but a combination of vocal excellence and an absence of obvious Italian rivals has allowed each to rise to the top in this repertoire. The quality of singing, especially in terms of musicianship, is outstanding, even when native Italian passion is lacking...Overall, a recital of distinction.

Their voices fit like a glove here in the Don Carlos duet...Like Milnes and Domingo, they’re quite close in timbre, so the bond of friendship seems especially strong.

From the good-natured but broken-hearted sparring of Rodolfo and Marcello in the opening duet from La Bohème (where these two mature voices sound rather more hard-bitten than many of their rivals on disc) to a properly chilling account of the great confrontation from Otello, this recital is a superb testament to one of today's most electrifying operatic partnerships - with Pappano's Santa Cecilia orchestra providing a wealth of subtle detail and bags of dramatic impetus. Unmissable stuff.

Whether as sworn foes in La Forza del Destino, devoted friends in Don Carlos or puppet and master in Otello, Kaufmann and Tézier give performances of total conviction and passion with Pappano and the Santa Cecilia orchestra empathetic enablers. Each duet evokes past productions or whets the appetite for future ones.