He added that he was shocked at being left out of the team for the 4-0 defeat by Germany in their Group D opener.
"Definitely I expected to play but it didn't turn out that way," Kennedy told reporters at Sydney Airport on Friday.
"We lost 4-0 so obviously those tactics for that game plan didn't work."
The Socceroos went out of the World Cup on goal difference despite a subsequent 1-1 draw with Ghana and a creditable 2-1 win over Serbia.
Kennedy came off the bench against Ghana and started in the surprise victory over Serbia.
"Me up front with Timmy (Cahill) behind, it's always worked," the Japan-based forward said. "He's always scored or I've always scored goals when we've played together.
"At times it's not the prettiest football but it works. We showed it worked against Serbia."
Cahill insisted Australia could holds their heads high after Germany and Ghana advanced from their group to the last 16.
"People see it as somewhat of a failure but I look at it as we've achieved something, because it was a bad start but we picked it up and did really well," said the attacking midfielder who helped Australia reach the knockout stages in 2006.
"I'm definitely gutted but, the thing is, it is what it is and you've got to get on with it.
"It's probably one of the weirdest experiences for me as a footballer, having such a weird start in the World Cup and nearly being over, to finishing on a high.
"I think there are so many positives, the young guys that came through. Yes, we might have a few older players retiring, but I'm positive for Australian football.
Cahill added: "It's not going to be easy but, the thing is, we've got potential."
‘The pure simplicity of the way Slot has managed the squad is probably the biggest thing I could say about him. It’s not broken, so let’s get on with it’: Liverpool legend full of admiration for Jurgen Klopp's successor at Anfield
‘I trained at Spurs and thought they’d give me a chance. But I received a letter thanking me but saying they didn’t think I was good enough – I was gutted’: How Tottenham missed out on signing Wales legend John Toshack
