Slaven Bilic has said West Ham must make high-quality signings after they were linked with Manchester City's Kelechi Iheanacho and Pablo Zabaleta.
An indifferent performance this season at one stage saw Bilic's side flirt with the Premier League relegation zone.
Speculation over new recruits has begun ahead of their final game of the season against Burnley on Sunday, and Bilic says he wants players who will improve his team rather than merely add numbers to his squad.
West Ham have recently been linked in media reports with City striker Iheanacho and full-back Zabaleta. The latter will be available on a free transfer after announcing he would end his nine-year spell at the Etihad Stadium.
When the names of both players were brought up in his pre-match press conference, Bilic was adamant West Ham must only acquire new additions who will have an immediate impact.
"We don't need squad players," the West Ham manager said.
"Take our last game against Liverpool. We were without eight players but still had a decent team so that shows that squad-wise, with the quantity of the players, we are okay. We would like to improve the quality in certain positions but I don't want to talk about names now.
"But hopefully we are going to be successful in finishing those transfers. Most of the players are linked with West Ham, the big majority of those are rumours, there's no truth in them."
West Ham great Sir Trevor Brooking backed the possible signing of Zabaleta this week, telling BBC 5 Live the Argentinian's leadership qualities would benefit the club.
However, Bilic was adamant his current squad have enough leaders in the dressing room who have helped with overcoming difficult periods this season.
"We have leaders on our team," Bilic said. "We have good vocal leaders on our team and we also have a good core of British players who are leaders plus some foreigners who are skippers in their teams.
"They are also the reason why we made it in very difficult times. Every time that was difficult for us and we needed to show that character before a game, we did it.
"Starting with Mark Noble of course who is a great captain, (James) Collins, (Winston) Reid, (Andy) Carroll when he was there. Players like (Jose) Fonte who was captain of Southampton long enough in the Premier League, so we are good in that."
Bilic said the club have activated an extension clause in goalkeeper Adrian's contract, which was due to expire this summer.
The 30-year-old was demoted to second choice behind Darren Randolph following a dip in form, but the Hammers will keep the Spaniard on their books for an extra two years.