Kewell has moved quickly to shake things up in his new club's squad, bringing in both young and experienced players to the English League Two side.
Two new faces are former Manchester United defender Cameron Borthwick-Jackson, ex-Manchester City goalkeeper Ian Lawlor, Bobby Grant from Wrexham, Portuguese defender Sido Jombati and Carl Piergianni - and more than one of them highlighted Kewell as one of their major attractions to the Oldham project.
"The excitement I got from the gaffer in the way he wants to play, the style of play and the enthusiasm - it was a no-brainer for me," Grant said.
Lawlor was likewise effusive in his praise for Kewell, saying: "I had a call from my agent saying there was interest from Oldham, I'd also heard the new gaffer had taken over and I was really keen to have a conversation with him.
"We'd spoken over the phone a couple of days ago - and then briefly the day before signing as well - and as soon as I had that conversation, his mindset, his ambition and his worth ethic, I was really keen on coming here.
"It's a chance to work with him, improve and give my all for this club."
Kewell has a very tough task in taking over Oldham, who are flirting with relegation into non-league football amid ongoing ownership issues.
Oldham have had six coaches in the last 19 months, including Man United great Paul Scholes, who quit after only five weeks citing "managerial interference" from the owner.