Cahill explained that he was 'buzzing' after making his senior debut against Bulgaria, and Knight knows exactly how the 24-year-old felt having played for England himself against USA and Colombia back in 2005.
Knight told the Bolton website: "I'm over the moon for Gary because he has fully deserved that cap, and I'm not just saying that because he is one of my mates.
"I bet he has received a million and one messages to congratulate him, but I haven't phoned or texted him yet - I will wait until I see him considering that I'm with him almost every day!
"He has shown how determined he is having been named in plenty of other squads but now he has got what he really wanted and his hard work has paid off. Hopefully it is the first of many."