Dress down

We are disappointed with the performance of the team but it does not mean that we are thinking of removing Dhoni as Twenty20 captain," a top BCCI source stated.
The Indian team, which lost all three matches in the super eight stage, returned home and will have to face some tough questions.
The cricketers avoided eye contact at the Mumbai and Delhi airports with the waiting media and slipped into their vehicles without offering any comments. Dhoni chose to make a quiet back door exit.
The team's arrival came a day after reports that coach Gary Kirsten had spoken to seven cricketers individually and complained about their fitness and commitment.
On his arrival in Mumbai, team manager Ranjib Biswal denied that the players had got a dressing down from Kirsten.
Nothing happened. We were all together at the team hotel before departing for home," Biswal stated.

Please explain to me the emboldened parts.

Source : http://cricbuzz.com/cricket-news/26331/Dhoni-will-not-be-replaced-as-captain--BCCI

Though I know usually it means " to wear informal clothes on an occasion to avoid attraction"