Gylfi Sigurdsson would leave Swansea "with a heavy heart" if his proposed transfer to Everton materialises, according to ex-boss Brendan Rodgers.
The Celtic manager was the man who first brought the Iceland midfielder to Liberty Stadium on loan from Hoffenheim in 2012, when Rodgers was in charge.
Everton have yet to match Swansea's £50m valuation for the 27-year-old.
"Gylfi is an outstanding player and if he was to go I know it would be with a heavy heart," Rodgers said.
"I took him to Swansea firstly on loan and I know how much it means to him. He's been a great servant there and currently still is until anything changes."
While Rodgers is not sure whether Sigurdsson will leave Swansea - who he rejoined permanently from Tottenham in 2014 - in this transfer window, the Celtic boss is sure that the Welsh club have plans to fill any gap created.
"If Gylfi does go - and it's a big if at the moment - I'm sure the scouting and recruitment team will have the people behind the scenes they want to bring in," added Rodgers, who was back at Swansea for Swans legend Alan Tate's testimonial.
"The strength of Swansea has always been the team. It lost individuals when I was there, players moved on, but the strength of Swansea is it's one team with one club."