West Ham joint-chairman David Sullivan has claimed that manager Slaven Bilic turned down the opportunity to sign Renato Sanches and Grzegorz Krychowiak.
Swansea and West Brom both pulled off impressive loan moves in the transfer market this week, with the Swans bringing in Sanches from Bayern Munich and the Baggies securing Krychowiak from Paris Saint-Germain.
Both players could have ended up at West Ham this summer, according to Sullivan, only for Bilic to reject the chance to add them to his squad, which currently sits bottom of the Premier League table.
"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," Sullivan is quoted as saying by Sky Sports.
"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."
Sullivan also revealed that West Ham turned down a last-minute opportunity to sign William Carvalho from Sporting Lisbon, having previously lodged an unsuccessful bid for the midfielder earlier in the summer.
"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," he said.
"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."
West Ham brought in a number of new signings over the summer, including Joe Hart, Pablo Zabaleta, Marko Arnautovic and Javier Hernandez, and Sullivan says Bilic is pleased with the additions.
"Overall Slaven is happy with the business we have done during the summer transfer window," Sullivan added. "We received the manager's wish-list before the window opened and we have managed to get the top four players on it."