The two clubs agreed a fee - believed to be £7million - for the defender last week but Cahill has stayed in the north west and played in crucial games against Wolves and Everton.
He will be rested for Saturday's FA Cup third-round trip to Macclesfield and, although Coyle was keen to stress that was not linked to the potential transfer, it appears almost certain Cahill's last act as a Bolton player will be the winning goal he scored at Goodison Park on Wednesday.
Coyle said: "Gary Cahill will be one of those to miss out on the game, and it's nothing to do with the continuing speculation regarding Chelsea. He's one of a number of players that probably needs to rest given the amount of games they've played.
"And moving on to that, my own opinion is I think there's a chance the deal can be concluded by the end of the week. That's where we're at but I'm not a party to any continued dialogue between Chelsea and Gary's representative.
"They were respectful of the other night, the fact we had a big game against Everton and that kept Gary focused and he showed his quality by doing that in the game."
Meanwhile, Coyle again denied any other club have come in for Cahill after speculation Manchester United were interested.
The Scot said: "When there's a continued conjecture and everything that goes with it people are always going to throw up names. There hasn't been any dialogue between ourselves and Manchester United or anything like that.
"We as a football club agreed a deal with Chelsea Football Club and for me that's binding. The only way that will fall down is if the relevant parties don't agree. But my own feeling is I'm pretty sure they can get to a place that they're all happy."
Bolton go into the cup tie on a high thanks to Wednesday's victory, which lifted them off the bottom of the Premier League table and to within one point of safety.
Even Everton boss David Moyes was happy to admit it was a deserved win for the visitors but they had to do it the hard way after going behind to a freak goal from Toffees keeper Tim Howard in the second half.
It was a very windy night and a long kick from the American caught a gust and bounced over the head of Bolton counterpart Adam Bogdan, who was making a rare Premier League appearance with Jussi Jaaskelainen sidelined by a thigh injury.
Coyle attached no blame to the Hungary international, who will start on Saturday, and praised his whole team for the spirit they showed to come back and win the game.
"It would have been easy after losing that freak goal to lose by two or three goals but nothing could have been further from the truth," he said.
"You could see they knew they were playing well, they knew they could breach the Everton rearguard, and we scored two very good goals.
"Young Adam Bogdan was outstanding in the game. We know he's going to be a top goalkeeper and I think he showed real character. Every ball that came into the box after that he dealt with."
Cahill will be one of five or six first-team regulars rested by Coyle, who received some more positive news on the injury front with defender Tyrone Mears back in training for the first time after breaking his leg in August.
The Trotters went all the way to the FA Cup semi-finals last year before losing 5-0 to Stoke, and Coyle knows a trip to Moss Rose will present its own challenges.
He said: "I've been in their position, I've been the underdog, so I know how it works. Macclesfield will have that extra 20-30% in their play so we'll have to be at our very best to progress.
"We're fortunate in the Premier League to have all the facilities and the grandeur that goes with it, but I started as a 13-year-old at a part-time club so I know what it's like, and I love that, because for me that's the real grassroots of football.
"I'm led to believe the dressing room is very small but that's the beauty of the cup and we'll be very respectful of it."
