Yevgeny Mironov's Pretender was a genius performance by the actor at the dawn of his national fame.
Boris Godunov should have been renamed The Impostor – that's how good Yevgeny Mironov is in the role of Grishka Otrepyev.
For Yevgeny Mironov, [Donnellan] has designed the central and best role in the show, and one of the best in Mironov's repertoire. ... It is a role that calls for genuine transformations, which Mironov delivers brilliantly.
Yevgeny Mironov plays one of his best roles in this production. His Pretender is an imp, a shapeshifter, a creature devoid of traits. His face and manner change instantly and unpredictably; ... in a few minutes he lives through a dozen states of being. In essence, his highly complex role is what gives meaning to Donnellan's austere layout.
... What stays [with you] are scenes of incredible keenness and precision, such as the famous Fountainside Scene, and the cold and brilliant power of Yevgeny Mironov's transformation from the pretender Grishka to Czarevich Dmitry. ... The whole enormous range of Pushkin's scene is gained with ease and bravura. It's been a long time since our stage has seen an acting duet of such beauty. ... In his Dmitry, Mironov unequivocally emerges as the consummate Donnellan actor – sober, precise, unsentimental and piercingly reactive: he does not miss out on a single possible motivation, emotion or inner monologue.
Mironov works with defiant ease. ... His animal instinct against triteness and excess, the sense of style and humor he acquired under Tabakov's masterly guidance, permit him a degree of sassiness that borders on insolence. You admire him like a soccer player on the level of Pelé or early Maradona, scoring goals like it was child's play while evading the defense with dazzling aplomb. This is why applause accompanies his every exit, why he can hobnob with the audience and momentarily drop out of character to wink at the pretty girl in the third row. "You, Mozart, are a god, and know it not."
Yevgeny Mironov demonstrates a dizzying mix of disarming sincerity and cynical insidiousness, of romanticism and scorn; utterly unpredictable, he is real at every turn.
Grishka Otrepyev as played by Yevgeny Mironov is dynamic and magnificent.
Yevgeny Mironov is practically a shoo-in ... for Best Actor.
Yevgeny Mironov's Impostor is possessed of internal plasticity and a hypersonic changeability of inner states. In his mouth, Pushkin's verse retains its cadence yet is so light that the subsequent prose sounds unnaturally clunky.
This performance has been lauded by all who have written about Boris Godunov, whether or not they liked the show on the whole. That Yevgeny Mironov is one of the heavyweights of today's stage is nothing new. We've got nobody else like him: I am speaking now not of the quantity but the quality of his gift. Normally, thespian talents spring up in a cluster, all at once and in a felicitous lineup, as though in answer to a call to action. That's what they call a "generation". But Yevgeny Mironov doesn't come as a matched set. His qualities remain unique – for all that they include not just a sense of partnership but a downright hunger for sparring: Mironov onstage is instantly responsive, quick to engage, at ease in paradoxical, provocative, embroiling transitions. The actor is astoundingly perceptive in all that concerns his character's emotional essence and rationale, for all that his technique is not at all that of psychological consistency – first and foremost, he uncovers the detonation points, the logic of eruption. The excitability of his artistic nerves and its effect on him are musical, hence the grace and the perfect pitch. He is stirringly and beguilingly real, albeit trueness to life is seldom among his stage objectives. ... His truth is the truth of artistry. His roles are not a confession, not even a partial revelation; the fusion here is of a very different sort. An old-fashioned expression seems apt – "surrender to the role". He surrenders to his role and its demands with ecstasy: obedience to dictates, internal or external, is in his artistic nature.
Only one argument can be put forth against Yevgeny Mironov as the Pretender: it was a predictable choice. From the point of view of acting, Mironov's work is flawless and astonishing.

[Translated by Vlada Chernomordik for the Yevgeny Mironov Official Website]