Fast bowler Mitchell Starc has been warned by captain Steven Smith to let out his frustration in other ways after he threw a ball at New Zealand batsman Mark Craig on the final day at the Gabba. Smith said the incident was "pretty disappointing", and he noted that it was not the first time Starc had failed to keep his cool and thrown a ball in a batsman's direction.
The incident occurred in the 84th over as New Zealand's final pair, Craig and Trent Boult, were holding off the Australians in their push for victory before lunch. Craig had just struck two consecutive fours off Starc and the third ball of the over was pushed back to the bowler, who gave away four overthrows by directing his throw close to the batsman and not the stumps.
Starc was fined 50% of his match fee by match referee Roshan Mahanama over the incident, after he admitted breaching Article 2.2.8 of the ICC Code of Conduct, relating to throwing a ball at or near a player in an inappropriate and/or dangerous manner.
"I thought it was pretty disappointing," Smith said. "He's done it a few times and I'm going to have a word with him when we get back down in the sheds. I don't think it was necessary at the time. Hopefully he can improve and get better from that.
"I don't think he needs to apologise. I just don't think he needs to do it in the future. There wasn't an opportunity for a run-out there and I think it was just a bit of frustration. I think he needs to let it out in other ways."
There was no obvious apology from Starc to Craig, who at the time was still firmly in his crease and was some distance from the stumps. As the players left the field following Australia's win, Starc shook hands with the batsmen Craig and Boult, but again there appeared to be no exchange of words between Starc and Craig.
"I thought the game was played in really good spirits, and I'm sure the rest of the Tests will be as well," New Zealand captain Brendon McCullum said after play. "We're about half an hour away from having a few beers downstairs with them as well, so that will be good fun.
"But the way I looked at it, I hoped he was trying to aim at the stumps. If that was the case and it just slipped out then so be it, we'll give him the benefit of the doubt."
The final day was also marred by a poor umpiring decision that ended McCullum's run-a-ball innings on 80; he was given out caught at slip but the ball had touched only his pad rather than his bat. New Zealand had unsuccessfully used their final review in the previous over, and they were only nine balls away from having the reviews replenished at the 80-over mark.
"That's the game," McCullum said. "Both Nigel Llong and Richard Illingworth are two of the best umpires in world cricket. They're outstanding umpires who are allowed to make the occasional mistake. That's just the game that you play and you've got to cop it sweet. We had two reviews which we used for decisions that could have gone either way as well. No regrets there."

Brydon Coverdale is an assistant editor at ESPNcricinfo. @brydoncoverdale