Cape Town - Dani Alves says Paris Saint-Germain must see reward for their investment with a sustained Champions League run this season.
PSG were drawn in Group C of this year's group stages, alongside Liverpool, Napoli and Red Star Belgrade.
The French champions, who have spent heavily in their bid for European success, travel to Merseyside on Tuesday to face last season's losing finalists Liverpool.
And Alves knows PSG need a significant improvement on last season to make an impact.
Thomas Tuchel's side have won their first four Ligue 1 games, and play Saint-Etienne on Friday.
But already looking ahead to next week, Alves told Omnisport: "We need to be careful for the next game [against Liverpool] because we play against a bigger, bigger club and this competition is very, very hard."
PSG reached the round of 16 last season where they were knocked out by eventual winners Real Madrid.
Alves added: "For this reason we have to be a little bit more careful then other matches but we accept the challenge from the group and competition and we need to do something different to last season."
"I think for PSG - for any club - to invest in players, in staff... you go home in the first challenge in this real competition, it is not good.
"It's not good for me, it's not good for the club and it's not good for us and we need to change something. Mentality shows what we do but in this year [we have] no chance to falter."