West Ham Slaven Bilic turned down Renato Sanches and Grzegorz Krychowiak, while a U-turn from Sporting CP on William Carvalho came too late for a club-record deal to be done, joint-chairman David Sullivan has revealed.
Bilic's men have made a dreadful start to the new Premier League season having lost their first three games.
The pressure on Bilic already appears to be mounting after their 3-0 defeat to Newcastle United last time out but West Ham did not add to their squad in the transfer window in the wake of that loss.
Joe Hart, Pablo Zabaleta, Marko Arnautovic and Javier Hernandez all joined the club earlier in the window, leaving Bilic seemingly content to reject midfielders Sanches and Krychowiak, who joined Swansea City and West Brom on loan from Bayern Munich and Paris Saint-Germain respectively.
Sporting reportedly rejected an offer worth an initial €30million with a further €10million of performance-related variables for Portugal international Carvalho.
Sullivan said the Portuguese side changed their mind on the final day of the window, but with not enough time for the transfer to be completed.
"Overall Slaven is happy with the business we have done during the summer transfer window," Sullivan told West Ham's official website.
"We received the manager's wish-list before the window opened and we have managed to get the top four players on it.
"It is no secret that we made a club-record bid for Sporting Lisbon's William Carvalho but unfortunately that offer was rejected a couple of weeks ago.
"Late last night [Thursday] Sporting Lisbon made contact to accept the original offer, but unfortunately it was just too late in the day, and we simply did not have enough time to put the player through a medical.
"We were not prepared, as a club, to buy a player for that amount of money without him having gone through adequate medical checks.
"Grzegorz Krychowiak and Renato Sanches were both offered to the manager before their switches elsewhere, but he told us that he is happy with the squad he has.
"As a board we are behind Slaven, and he believes he has the tools to turn around our form and rectify our disappointing start to the season."