Racing 92 owner Jacky Lorenzetti said on Monday former South Africa captain Siya Kolisi was "invisible" in the weekend's French Top 14 play off defeat to Bordeaux-Begles.
The Parisians lost 31-17 on Sunday condemning back-rower Kolisi to a trophyless season in his first campaign with the club after April's Champions Cup last-16 loss to eventual winners Toulouse.
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"He put on a few kilos, lost his form and yesterday he was invisible," Lorenzetti told specialist website Rugbyrama.
"We missed him," the 76-year-old added.
Kolisi, who told AFP last week he had gained 5kg (11 lbs) before losing it again, arrived in the French capital after lifting a second straight Rugby World Cup with the Springboks.
The 32-year-old was brought in by six-time French champions Racing on a two-year deal as a replacement for, among others, ex-France flanker Wenceslas Lauret.
"At back-row we had been used to seeing an ultra-present warrior like Wenceslas Lauret," Lorenzetti said.
"For now, Siya isn't making us forget him. But we think next year, it will change," the Frenchman added.
In further news, Former France prop Patrice Collazo will leave his role at billionaire-backed Montpellier after guiding the club to the Top 14 safety.
Ex-Brive, La Rochelle and Toulon coach Collazo took over the 2022 champions in November from Englishman Richard Cockerill on a two-year deal as disgraced former French Rugby Federation president Bernard Laporte was appointed director of rugby.
"We knew too well it was short term," Collazo told Sud Radio later.
"That's why I accepted the assignment from Montpellier," the 50-year-old added.
Montpellier, owned by outspoken Mohed Altrad, finished 13th in the league and needed to beat Grenoble in Sunday's relegation play-off to avoid dropping to the second division.
Altrad will hold a press conference on Tuesday to confirm the details with the club's former scrum-half Benoit Paillaugue in line to come into the coaching set-up.
