A petition calling for Real Madrid to sell him this summer has surpassed one million signatures.
A spokesperson for the 27-year-old France captain issued a statement to AFP rejecting the premise of the backlash.
"Part of the criticisms are based on an overinterpretation of elements related to a recovery period strictly supervised by the club. This is not corresponding to the reality of the commitment and the work that Kylian does daily for the good of the team."
Head coach Álvaro Arbeloa was also defensive of the player after Sunday's 2-0 win at Espanyol, noting that the medical staff determine the schedule for injured players and that free time outside those sessions is the player's own.
The trip to Sardinia was not, by itself, in breach of any protocol — Mbappe, Thibaut Courtois and Arda Güler were all granted rest days by the club. The issue for some within the Bernabéu is one of optics and timing, coming as Madrid face losing La Liga for a second successive season and prepare for Sunday's Clásico against Barcelona.
Separate from the holiday controversy, L'Equipe has reported that Mbappe's dressing room standing has been damaged by a pattern of behaviour over several months — arriving late to a team meal, socialising primarily with his fellow Frenchmen, and a training ground incident in which he spoke angrily towards a member of Arbeloa's coaching staff acting as a match referee.
Further friction came when Mbappe liked and then unliked a social media graphic linking José Mourinho to the vacant permanent manager position. Asked about it, Arbeloa was dismissive: "I am indifferent to whether Mbappe likes Mourinho, Julia Roberts, or anyone else."
The petition, launched with the slogan "Madridistas, make your voice heard," had gathered more than 1.2 million signatures by Tuesday afternoon. Mbappe has scored 41 goals in all competitions this season — the most of any player at the club — and leads the scoring charts in both La Liga and the Champions League.