Brendan Rodgers welcomed Jozo Simunovic back to Celtic "with open arms'' and suggested fate could have been behind his failed move to Torino.
The 22-year-old Croatian defender travelled to Italy for a medical, but the transfer collapsed late on deadline day.
Some reports claimed that the Serie A club had reservations following the medical checks, but Simunovic, using his Twitter account, stressed that his results were "perfect'' and that his "head is in Celtic and I am 100% focused on the field and the challenges ahead''.
The former Dinamo Zagreb player, who moved to Parkhead a year ago, has not played since January after suffering a knee injury, but he has recently resumed training.
Speaking to CelticTV, Hoops boss Rodgers was asked if Simunovic would have the opportunity to challenge for a place in the side.
He said: "Yes. I haven't seen a lot of Jozo, so I haven't seen his entire qualities, but he is just coming back to fitness.
"He has trained a couple of times with the team and I like what I see.
"He obviously has a long way to go in terms of that physical fitness as he has been out for so long.
"But he is a young player, he is very hungry. I like him as a boy.
"Obviously the move didn't work out for him or the club, but maybe it was fate.
"Maybe he is meant to be back here, playing, working and we welcome him with open arms back to here and let's see if he can produce good performances for Celtic.''
Rodgers brought in Moussa Dembele, Kolo Toure, Scott Sinclair, Dorus de Vries and Cristian Gamboa during the transfer window.
Celtic's only deadline-day business was to loan right-back Saidy Janko to Barnsley for the season.
However, with £30 million of Champions League money having been earned, there were some eyebrows raised when the deadline passed without another recruit, with Everton midfielder James McCarthy linked with a move to Parkhead.
Rodgers said: "I wanted to bring in another creative midfield player to support the boys we have here, but I will never bring in anyone for the sake of bringing in a player.
"It has to be the right player, has to be the right profile, otherwise you waste time, money and energy
"We tried everything we could to get the right quality of player, but the players were not available and you can't get a player if a club doesn't want to sell them or loan them.
"I am delighted with the players we have here.''