The Australian has been one of the Merseyside club's most reliable sources of goals over the last four years. But Fellaini, a £15million signing at the start of the season, has proved that he can also find the net from midfield, leaving manager David Moyes with a selection dilemma for Sunday's Goodison Park clash with Middlesbrough.
While Cahill is raring to go, Fellaini is also available after serving a one-game ban last weekend and the two players are not necessarily easy to accommodate in the same line-up.
Cahill knows he has to prove he deserves to keep his place in the starting line-up. "I'm all for it," he said. "I think the best thing for me is to welcome players like Marouane with open arms. I'm happy for him because with a price tag like that people expect him to come in and do things straight away. It's up to us to help him settle and make sure he scores more goals."
Cahill missed the start of this season as he recovered from a broken foot, but he is now back to full fitness and started both of Everton's recent wins over Fulham and West Ham. "Our aspiration is to finish in the top eight and then build on it," Cahill added. "The sooner we get near to the top of the table then anything can happen.
"As you can see, everyone is beating everyone. I feel that everyone wants to win something and everyone wants to do well. So if you are anywhere in the top eight in the next three to four months, then anything can happen."