Arnold’s Sky Blues downed City 1-0 at AAMI Park on Friday night, however an injury to Cahill early in the first half stole the headlines as he left the pitch after a challenge on Jordy Bujis in the 22nd minute.
It appears Cahill rolled his ankle and may be in doubt for the Socceroos’ final World Cup Qualifier reverse fixtures against Honduras.
And the Sydney boss, who has worked with Cahill in the Socceroos, said that he might have opted for a different approach to his counterpart Warren Joyce.
“I was actually surprised he started, I thought he was going to be away for the next few weeks, but I don’t make those decisions,” Arnold said post-match.
“At the end of the day, as a coach, I probably would’ve planned a bit different because he wasn’t going to be here for the next three weeks anyway, it’s not my choice, it’s Warren’s.
“The first thing I thought of straight away was the national team. Timmy’s our star, you can’t give too much credit to someone who does so much for the country.
“What he did against Syria, 120 minutes, what he did was phenomenal. Let’s all keep our fingers crossed he’s OK.”
Joyce was adamant post-match he was unsure what the specific injury was.
The City manager denied the Socceroo had any problems going into the game and also said Socceroos boss Ange Postecoglou had not contacted him prior to the match.
“The national team coach has got no bearing on that,” Joyce said.
“Timmy is desperate to play, he’s training hard. It’s a big game, we’re trying to win a big game.
“We just had things we wanted to do, ways we could hurt them, I thought he was useful for the side to do that.
“We’re trying to win a football match, he’s a Melbourne City player, he’s desperate to play in a football game against a big team and win the game. That’s his objective and my objective.”