Arzani, Karacic named in Socceroos' initial World Cup squad
Arzani, 19, enjoyed a fine A-League season, doing enough to impress coach Bert van Marwijk to be part of the 32-man squad.
The tricky winger scored two goals and provided three assists in the league this campaign, leading to suggestions Iran – his place of birth – could poach the teenager.
Meanwhile, Cahill is on track to play at his fourth World Cup despite limited game time at Millwall.
The 38-year-old striker's spot has been a talking point, but he was included despite playing just 63 minutes in the Championship since his return to the club in January.
Our preliminary 32-man squad for the 2018 @FIFAWorldCup #GoSocceroos pic.twitter.com/BBdBbnyXy1
— Caltex Socceroos (@Socceroos) May 7, 2018
Among the surprise selections was Fran Karacic, the 21-year-old NK Lokomotiva right-back.
Karacic was born and has played his entire career in Croatia, but appears set to don Socceroos colours.
"I am not a person who changes all the time and we thought for a long time about the first squad that we selected," Van Marwijk said.
"I had a good experience with the 26 players in the 10 days that I worked with them [for friendlies against Norway and Colombia], so I had no reason not to nominate them again. But we have since seen other players so there will be a few new names in the squad."
Australia: Brad Jones (Feyenoord), Mitchell Langerak (Nagoya Grampus), Mathew Ryan (Brighton and Hove Albion), Danny Vukovic (Genk); Aziz Behich (Bursaspor), Milos Degenek (Yokohama F Marinos), Alex Gersbach (Rosenborg), Matthew Jurman (Suwon), Fran Karacic (NK Lokomotiva), James Meredith (Millwall), Josh Risdon (Western Sydney Wanderers), Trent Sainsbury (Grasshopper), Aleksandar Susnjar (Mlada Boleslav), Bailey Wright (Bristol City); Joshua Brillante (Sydney FC), Jackson Irvine (Hull City), Mile Jedinak (Aston Villa), Robbie Kruse (Bochum), Massimo Luongo (QPR), Mark Milligan (Al Ahli), Aaron Mooy (Huddersfield Town), Tom Rogic (Celtic), James Troisi (Melbourne Victory); Daniel Arzani (Melbourne City), Tim Cahill (Millwall), Apostolos Giannou (Guangzhou R), Tomi Juric (Luzern), Mathew Leckie (Hertha Berlin), Jamie Maclaren (Hibernian), Andrew Nabbout (Urawa Reds), Dimi Petratos (Newcastle Jets), Nikita Rukavytsya (Maccabi Haifa).