La Rochelle captain Will Skelton said his side "weren't good enough" after they were beaten 25-24 at Castres in the French Top 14 on Saturday a week after being knocked out of the Champions Cup quarter-finals.
The two-time Champions Cup winners, coached by former Ireland fly-half Ronan O'Gara, were hammered by Leinster last Saturday but still move up to fourth in the French table thanks to the bonus point with five rounds of the regular season to play.
Catch every game of the Super Rugby Pacific LIVE on Stan Sport. Start your Free Sport Trial Now
"We wanted to send a message here, but we weren't good enough," Australia lock Skelton told reporters.
"We were very proud to play the quarter-final of the best club competition in the world, the emotion was high, and the fall after was just as steep," he added.
Young winger Nathanael Hulleu crossed twice in eight minutes for the home side, who move up to sixth place, the final play-off spot, with their first win in five games in all competitions.
Former New Zealand scrum-half Tawera Kerr-Barlow was missing for O'Gara's side after suffering a head knock against Leinster.
Despite Kerr-Barlow's absence La Rochelle led 14-13 at the break thanks to an impressive solo try from Samoa centre UJ Seuteni.
Hulleu's double in the final 15 minutes swung the game in Castres' favour as the 23-year-old took his try tally to nine for the season.
Elsewhere, ex-All Blacks winger Leicester Fainga'anuku crossed for his sixth try in seven matches as 14-man Toulon held on to beat second-placed Toulouse 20-19 in front of more than 60,000 people at Marseille's Velodrome, the venue for this season's Top 14 final.
Seuteni's Samoa team-mate and lock Brian Alainu'uese was shown a red card just before half-time for a high tackle but Toulon move up to fourth with the win.
Toulouse were without star scrum-half Antoine Dupont, who is away with France's sevens set-up before this summer's Olympic Games.
"Sometimes you have to know how to win ugly," Toulon scrum-half Baptiste Serin told Canal Plus.
"Tonight we weren't flamboyant, far from it but we didn't give up," he added.
Earlier, leaders Stade Francais needed an 81st minute try from No 8 Giovanni Habel-Kueffner to beat Bayonne 28-24.
At the other end of the table, bottom side Oyonnax moved nearer to relegation losing 43-13 at home to third-placed Racing 92, thanks to 18 points from South African full-back Tristan Tedder.
The Springboks' two-time Rugby World Cup winner Siya Kolisi was missing with an ankle injury for Racing in the week he was named among Time magazine's 100 most influential people of 2024.
Australian fly-half Jake McIntyre scored 19 points as Perpignan moved closer to safety hammering Lyon 51-20.
On Sunday, Bordeaux-Begles host Clermont a week on from their heartbreaking one-point Champions Cup loss to Harlequins.
