The Red Bulls Designated Player says that it would be massive blow for Everton if David Moyes leaves the club when his contract expires at the end of the year.
Moyes could look for other opportunities in the summer, following over 11 years with the club. Cahill, who left Everton for the New York Red Bulls in July, 2012, believes that Moyes is essential to the Toffees' success in the future and denies that Everton isn't a big enough club for the Scottish manager's ambition.
"A big job is Everton," Cahill said. "Whoever fills his shoes, if he goes, that's one of the biggest jobs in the league. But if he does go, I can't see... it would be very difficult for that person to fill in."
He added, "I think they'll be fighting tooth and nail to keep him because he's a hard man to replace."
Moyes and Cahill have a strong relationship, thanks to the manager's 2004 decision to take a chance on the then little-known attacking midfielder playing in the second division. Though scouts were impressed with Cahill's talent, many thought he would be too undersized to succeed in the Premier League. However, once Cahill arrived to Everton from Milwall for a bargain 1.5 million pounds, he immediately became a star under Moyes' guidance. Cahill scored 56 goals during his eight-year stay with the club.
Moyes has plenty of other stories and successes similar to his work with Cahill. Despite being one of thriftiest teams in the Premier League, Everton has been a mainstay in the top half of the league table and has qualified for the Champions League along with reaching a FA Cup final. The only knock on Moyes' resume is that he remains trophyless during his time in England.
Cahill stays in touch with Moyes on a regular basis but he wouldn't reveal whether Moyes had given him any indication of which way he's leaning. The only thing that the Red Bulls star did emphasize is that Moyes is vital part of Everton's history and that he knows Everton holds special significance for the manager.
"All I can speak on is what he's done and who he is as a person. He's very honest," Cahill said. "He's someone who's reached the heights and beyond the expectations of our football club. Whether he goes, is a different story."
He added, "Everton is a special club for me and I know it is for him as well. Who knows if he'll sign a new contract or not or whether there's something else there. I know during my time, it was a magical time and he's someone I'm still very close to. So I wish him all the best."
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