On Monday night, at American Ballet Theatre’s season premiere of “Giselle,” Nina Ananiashvili gave what is likely one of her last performances in one of her best roles, given that next season will be her last with the company. Like her legendary Bolshoi Ballet ancestor Galina Ulanova, Ms. Ananiashvili deviates from the classic portrayal of this innocent village girl betrayed by a callous aristocrat. For one thing, Ms. Ananiashvili is tall, and thus further from the prototypical image of a retiring and modest young girl. She uses her height and a certain propensity for flamboyance to add a refreshing note of assertiveness and even mischief.

No ballerina in her mid-40s is going to be in faultless technical shape, and Ms. Ananiashvili reinforced this on Monday night. But, to her credit, she didn’t cheat. She did, however, speed things up to mask diminished control and power in adagio. (This is assuming that conductor David LaMarche was taking things at the clip she had requested, since her natural inclination toward speed in recent years has seemed a strategic choice.)

In her Act 1 variation, the speed was jolting and excessive, even if she did conclude with a stage-encompassing circle of turns that frothed with bravura excitement. On the whole, she was better Monday night than she had been a year ago, when I saw her dance Giselle in New Haven with the company she now directs, the State Ballet of Georgia. On Monday, her arms were lighter and retained more Romantic style.

As the aristocrat who betrays Giselle but finds forgiveness from her in a transfigured postmortem, Angel Corella gave a characteristically erratic but ultimately creative and convincing performance. In Act I, Count Albrecht is both Giselle’s ardent suitor, disguised as a rustic, and a spoiled lord of the manor who bristles at any attempt to thwart his amorous masquerade. As ardent wooer, Mr. Corella was demonstrative, sometimes excessively so. Some of his shtick, such as a big wet kiss thrown at Giselle’s door after she’s stepped into her house with her mother, seemed like just that: shtick. He also resorted to some almost childish and nearly cartoonish ploys to proclaim his noble status, squaring his shoulders and puffing out his chest. But his figure was lithe and he paid careful attention to the line of his hands. His run offstage, fleeing the lifeless body of the betrayed-unto-madness Giselle, augured well for Act II.

In Act II, Giselle is on the verge of being conscripted into a sisterhood of Wilis, venomous wraiths who are the restless and predatory spirits of women betrayed before marriage. Here Mr. Corella immersed himself without visible calculation into the unearthly, weightless, and temporally arrested landscape of the Wilis. The wild impetuosity of his Act II solo may not be the most circumspect way to dance this piece but, nevertheless, it carried its own credibility, registering as the feverishness that is a real part of the Romantic temperament.

Gillian Murphy danced Myrtha, the queen of the Wilis, on Monday night. In her entrance, her bourrèes across the stage were infernally fast but not smooth enough to convince us that she was propelled by eerily inscrutable locomotion. She performed the solo adagio that follows too rapidly, diminishing its proprietary, majestic quality. I wondered whether her rigid back and angular arms in jumps were a question of her being more concerned with establishing the malevolent character of Myrtha than evoking the beauties of the choreographic conception.

Ms. Murphy’s performance was jarring because it existed in a completely different stylistic zone than that of her 18-member flock of subject Wilis and her two attendants, Moyna and Zulma, who were danced by Melissa Thomas and Zhong-Jing Fang, respectively. They danced within the movement and expressive parameters of Romantic ballet style, and did so very well indeed. In fact, Ms. Fang was one of ABT’s most expressive Zulmas since the unforgettable performances given by Kim Highton 25 years ago.