Slaven Bilic says West Ham’s problems will not be solved simply by making further signings.
The Hammers are bottom of the table after losing all three of their opening Premier League matches this season.
The Croatian is keen to add to his squad ahead of Thursday night’s transfer deadline.
But Bilic does not believe that the kind of shortcomings that were exposed in Saturday’s defeat at Newcastle were down to any need for new signings.
He told the club website: “It’s not about the transfer window. We were looking for one more player, but we had done a good job on paper in the transfer window.
“We made a good squad, a squad which looked good enough to have a good season.
“OK, it’s still early in the season, but it’s not about the transfer window. It wasn’t because of one player – we didn’t look good as a team.”
The team’s awful start to the season has led to speculation over Bilic’s future, with the club’s owners reported to be reviewing his position.
“This is a job about good times and bad times, and you have to show your quality as a manager more in the bad times than in the good times,” he said.
“We have to work very hard to come out of this situation. I’ve done it before, of course, and I have to do it again.”