Northampton may have lifted the Amlin Challenge Cup only a week ago but Stephen Myler insists the success of their season will be decided by Saturday alone.
Saints are hoping to secure their first Aviva Premiership title when they face strong favourites Saracens in front of a sell-out crowd at Twickenham.
Last year was their only previous appearance in the final, losing heavily to Leicester, and Myler admits it is time for Northampton to be crowned English champions.
"The league season is our acid test as a club and squad. We've progressed a lot this year, but it comes down to one day determining whether we've been successful or not," he said.
"That's bit of a funny scenario to be in, but it's what we must work hard for and hopefully we can do it. I believe it will come down to who plays best on the day.
"It's one each between us and Saracens in the league and we're expecting a tough battle, Saracens at their best.
"They have quality players, so I'm sure they're professional enough to overcome losing in the Heineken Cup final last weekend and get back on page for this game."
Myler was named man of the match against Bath in last Friday's European final, continuing a terrific season that could have seen him win his second cap in England's first Test against New Zealand on June 7 had be not been action against Saracens.