Midfielder Jack Cork says the Swansea City players are still adjusting to the departure of captain Ashley Williams.
The Wales skipper left after eight seasons with the club to join Everton for a fee approaching £12 million.
Francesco Guidolin’s side kept a clean sheet in his absence as they won their Premier League opener 1-0 at Burnley.
“Ash was such a massive part of this club and was the captain,” Cork told BBC Wales Sport. “We’re trying to move on now.”
Swansea are seeking to replace Williams, who was signed following the sale of John Stones, now the world’s second most expensive defender.
Last season’s top scorer Andre Ayew also left the Liberty Stadium in a £20.5 million switch to West Ham United along with strikers Eder, Alberto Paloschi and Bafetimbi Gomis.
Spanish striker Fernando Llorente and his compatriot, record signing Borja, have arrived to bolster the attack along with midfielder Leroy Fer, who scored the winner at Turf Moor.
Cork admits preparations for the new campaign have been difficult in the absence of Williams, who was given extra time off after helping Wales to the semi final of Euro 2016.
“It’s been tough. Ash was amazing – he was amazing with me since I came to the club,” Cork said.
“I was close to him and my family was close to him.
“It’s been a strange six weeks, really without him in pre-season and especially in the first game.
“When that goes it leaves a big void and everyone needs to step up and help each other and all of us try to be leaders because he was a big leader.”
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