Reigning champions Castres opened the new French season on Sunday as they had ended the last by beating Montpellier, although this time the finish was much tenser.
Castres entered last year's playoffs as the lowest seed but beat Montpellier, who had topped the regular season table, by 16 points in the final. This time they clung on with 14 men to win 25-20 away.
In recent seasons, the French champions have often started the next season badly and many have struggled over the whole season. No club has repeated as Top 14 champions since 2012 and only one, Castres in 2014, has even returned to the final.
"I'm fed up with this champion's curse, it exists if you believe in it, otherwise it does not exist," said Christophe Urios, the Castres coach. "Today, we are champion of nothing at all, it was important to make this understood by the players."
It was Montpellier's first home league defeat since May 2017.
"We were neither consistent nor realistic, unlike Castres," said 23-year-old No.8 Martin Devergie. "They did what they had to do to thwart us, like in the final."
Devergie gave the hosts hope of rapid revenge with a try after 18 minutes.
The champions hit back. They were level by the break with a try from French international Scott Spedding, a summer recruit from Clermont. They took control early in the second half with tries by lock Rodrigo Capo Ortega and a second by full-back Spedding, to lead by 12.
"It's a very good start," said Spedding.
Montpellier hit back when lock Paul Willemse burrowed over with 17 minutes left.
The hosts pressed furiously but even with Castres down to 14 for the last seven minutes, after Camille Gerondeau was shown a yellow card, could not find the breakthrough.
Montpellier made a string of handling errors and also crossed the line twice only for video reviews to rule out possible tries.
"It's not the result we expected for our first home game," said Vern Cotter, the Montpellier coach. "We had the chance to win it, but we're not a great team yet. A great team would have scored at the end to win."
- Italian talisman -
On Saturday, Stade Francais kicked off the Top 14 season thrashing newly-promoted Perpignan, 45-16, despite playing most of the match with 14 men while the other Parisian team, Racing 92 also won away, at Toulon.
Stade who only avoided relegation on the final day of last season have the biggest budget in the Top 14 thanks to Swiss billionaire owner Hans-Peter Wild, who has also hired former South Africa coach Heyneke Meyer.
On Saturday, they lost Italian talisman Sergio Parisse who was sent off shortly before half-time.
For Perpignan former Ireland half-back Paddy Jackson scored a try and a penalty on his debut
Another new arrival, Scotland fly-half Finn Russell, scored two tries and 20 of his side's points in an impressive 25-9 win at Toulon.
Toulon's half-back recruit, Welsh international Rhys Webb, had a less memorable afternoon. With his team trailing by six but with a 10-minute man advantage, Webb threw a loose pass that Racing's Juan Imhoff intercepted before racing away to score.
Toulouse snatched a 16-16 draw at last season's surprise semi-finalists Lyon, as France full-back Yoann Huget grabbed a crucial second-half try before Thomas Ramos' late drop goal secured two points.
Clermont's bid to put last season's dreadful title defence behind them got off to the perfect start, as former All Black Isaia Toeava and Fijian Alivereti Raka both crossed twice as they crushed Agen 67-23, scoring 10 tries in total.