Gallagher is yet to make a first-team appearance for Chelsea after spending last season on loan at West Brom.
The 21-year-old was on loan again this summer as he joined Crystal Palace and the thriving midfielder under Patrick Vieira at Selhurst Park.
Gilmour, meanwhile, struggled to make an impact on lending at Norwich City despite a strong start at Carrow Road.
The Scotland international impressed Thomas Tuchel in the second half of Chelsea’s campaign last season and Cech is confident both midfielders will return to Stamford Bridge in a “stronger position”.
“Conor was very close to being a part of the squad here this summer and we were really happy with him but it was the same as with Billy Gilmour and we felt at this point in their career that they had to go and play so much. as many matches as possible, ”Cech wrote in his Chelsea column.the official site of.
“They’re both at the stage where we really want them to be key players for Chelsea so it was better for them to go out and play.
“For Conor, getting England’s call was absolutely amazing and making his debut was obviously even more amazing. If he wasn’t going to Crystal Palace and play but rather stay here and maybe not play every game then that would never have happened.
“Once you start playing regularly in the Premier League and show what you can do, it gives you all these chances to be selected. If you have the opportunity to do that on a loan, you can get Chelsea back to a much better and stronger position.
“Conor will come back to us in a completely different situation than he was six months ago and that’s the beauty of it. If everything works out perfectly, that’s the underlying idea and it’s obviously great to see that it has worked perfectly for Conor so far.
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