The Wanderers centre-back made his senior international debut on Friday, coming off the bench in the second half of the Euro 2012 qualifier against Bulgaria to replace the injured Michael Dawson.
With Dawson sidelined, Cahill has been tipped to make Fabio Capello's starting line-up alongside Everton's Jagielka for tonight's fixture in Switzerland, and Coyle believes Cahill will be ready for the task, despite his relative inexperience.
"Anybody who has any qualms or reservations is entitled to their opinion but for me, both lads are top players," Coyle said.
"Recognising that Switzerland away is a tough game, I'm pretty sure that those two lads will be ready to cope with whatever they are asked to."
Coyle feels Cahill acquitted himself well against Bulgaria and hopes a start tonight will be the next step in a lengthy England career for the 24-year-old.
"He probably wanted to do everything straightaway as soon as he got on there, but I think when he settled into the game and did the simple things well, he showed what a top player he is," Coyle said.
"Fingers crossed he is playing tonight against Switzerland, and if he can do that, hopefully cement a place in the England set-up."
The player's stock is rising and Coyle acknowledges Cahill may leave Bolton before long but is aiming to retain his services for at least the remainder of this season.
"It's two-fold - first and foremost, we certainly don't want to lose Gary Cahill, but as I've mentioned before, there might very well come a time when he will outgrow the football club, because I think he could play for any top club worldwide," Coyle said.
"I think he'll get better, and if that time comes about, then Gary will go with my blessing as it will only be because he has played consistently well for Bolton Wanderers and hopefully for England that all those clubs are clamouring for him.
"If and when that comes about, the football club will look to do the best for themselves, but also recognising that Gary has to go and really flourish and take his career on.
"But that is not for now, certainly I hope it is not in January and we'll review that next summer, fingers crossed."
Source: Team Talk
Source: Team Talk