Football is won and lost in both penalty boxes - a lesson that was rammed down the throats of the Socceroos as they succumbed 2-1 to England.
There was a lot to like about Australia's performance at the Stadium of Light with Tom Rogic, Aaron Mooy, Brad Smith and Robbie Kruse - in particular - putting in promising displays.
But the concern for Socceroos coach Ange Postecoglou is that the visitors only tested England goalkeeper Fraser Forster once, while Australia's defence still has plenty of work to do to survive against the world's leading nations.
Without Tim Cahill - who will join up with the Socceroos for next month's two games against Greece - Australia lacks cutting edge in the forward third, with their goal on Friday coming from the head of England's Eric Dier.
Cahill was unavailable because the friendly was played outside FIFA's international windows.
For the same reason Postecoglou was denied the services of key defenders Trent Sainsbury, Matthew Spiranovic and Ryan McGowan.
It took England just two minutes to highlight their absence.
As the hosts attacked through the left channel, right-back Josh Risdon was sucked into midfield, which subsequently left centre-backs Mark Milligan and Bailey Wright with too much space to cover.
Raheem Sterling's attempted cross looped off Wright and it fell to an unmarked Marcus Rashford and the Manchester United striker volleyed home on his international debut.
Risdon was caught out of position a number of times in Sunderland and although Postecoglou has an attack-first mentality, his full-backs must be able to recover better than the Perth Glory man showed.
Milligan looked uncomfortable too - it's been a long-time since the Baniyas midfielder played in defence - while Smith was arguably the only member of the back four who produced an above-average performance.
Midfield was where Australia shone, however, with Rogic, Mooy and Massimo Luongo starting together for only the third time.
The Socceroos' high press meant England often struggled to play out of defence, with the visitors' trio of playmakers enjoying the repeated possession and showing off their skills in tight spaces.
Mooy and Rogic were the Socceroos' best players, with the latter looking particularly sharp - a great advertisement for his talent, if those scouts from Arsenal, Valencia and Fiorentina were watching.
There is no doubt Rogic, Mooy and Luongo are amongst Australia's most skilful players but England's joy on the counter-attack showed having that trio in midfield can leave Postecoglou's men short in transition.
England's second goal was a clear indication of that, with Wayne Rooney left all alone to smash the ball past Mat Ryan.
By comparison, Australia - for all their possession - didn't open up the home side's defence enough.
Forster only made one save for the match, Mooy teed up Kruse in the 71st minute but his shot was blocked by the Southampton goalkeeper's legs.
Jamie Maclaren barely saw the ball on his international debut, while Rogic should have tested Forster with at least one of his five shots.
Before the match, Postecoglou was keen to emphasise that the Socceroos' upcoming World Cup qualifiers would always be more important than any friendly.
But this was a reminder of what Australia will face if they qualify for Russia 2018 and although they showed they can mix it at the top level, work still needs to be done before the Socceroos can expect regular wins against the best.
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