Unai Emery said Paris Saint-Germain are seeking to add competition for places in the transfer window, with director of football Patrick Kluivert confirming the club will at least bring in one more player.
PSG have already signed Julian Draxler from Wolfsburg this month, while Argentine attacking midfielder Giovani Lo Celso - who they acquired in July - is now with the squad after his loan with former club Rosario Central ended.
But the defending Ligue 1 champions are still seeking further reinforcements.
Speaking after Wednesday's 2-0 Coupe de la Ligue quarter-final win over Metz, Kluivert told France Televisions: "Another player that's for sure, maybe two. The transfer market is very difficult. We do not want to buy to buy.
"It is important to buy a player to improve our team."
Kluivert also clarified the futures of Blaise Matuidi and Angel Di Maria, adding: "We also want to extend [the contract of] Blaise. Di Maria? Yes he will stay."
Emery revealed PSG are looking at adding more depth going forward, though he was pleased of the performance of substitute Hatem Ben Arfa against Metz.
"The club is looking to improve the team to give more competition. We talk a lot about the different possibilities but it is not an easy market," Emery said in his post-match media conference.
"If the club gives me a name and tells me that he is a very good player I say yes. We want to strengthen our attack, but the work of Hatem was good."
PSG have been drawn against Bordeaux in the semi-finals as they bid to win the Coupe de la Ligue for a fourth successive season.