Ben Stokes says he apologised to his England team-mates after his frustrations were evident during the second-Test defeat by Pakistan.
The hosts levelled the three-Test series on Thursday after wrapping up a 152-run win in Multan.
However, it could have been a different story but for fielding errors at crucial stages for the visitors, Jamie Smith and Joe Root notably dropping catches to dismiss Salman Agha, whose subsequent knock of 63 helped Pakistan seal victory with a day to spare.
Stokes, who returned to action following a hamstring injury, could not hide his frustration during a difficult day for England, but insisted he would not let his emotions get the better of him again.
"No one means to drop catches, but it just proves how important catches are in these subcontinent conditions, they don't come along that often," he told Sky Sports.
"I actually apologised to the group last night. It's the first time in my captaincy that I've let my emotions and how I was feeling with the way the game was unfolding show in my body language.
"I owned up to that and was very annoyed at myself for letting that out. It's something that I don't want to do or be seen to be doing, so I apologised to the group about that.
"Poor old me, I was a tired, grumpy old man last night! You won't see that happen again."
However, England coach Brendon McCullum defended the actions of his skipper.
"We all know how passionate Ben is, how much it means for him to play for England," he said.
"We've seen that through his bloody-mindedness to get back from injury, which was significant, and to do so in a nine-week timeframe and to have his first TM [Test match] in extreme conditions, 40 degrees, and be able to give what he gave to the side.
"I think, maybe, that's where some of that frustration led to - certainly, it wasn't directed at any of the players. It was more about trying to assess the rhythm of the game, and to impact on it."