Robin van Persie promised that he and his Heerenveen players would "keep playing our own game" and would not be "traumatised" after suffering a record 9-1 defeat at AZ Alkmaar in the Dutch league.

It was only the former Netherlands, Arsenal and Manchester United striker's fourth match as a manager after being appointed head coach of Heerenveen in May.

"This is tough," said the 41-year-old, who scored 50 goals in 102 international appearances.

"You'll encounter a number of bumps in your career. This was a very big bump. We learned a few more lessons from this match than we normally would."

Sven Mijnans opened the scoring for AZ after just four minutes but Luuk Brouwers equalised for Heerenveen midway through the first half.

Former Tottenham striker Troy Parrott, 22, soon put the home side back in front with his first goal for AZ since a £6.7m summer move from north London.

Things quickly turned sour for the visitors at the start of the second half as Republic of Ireland front man Parrott added a further three goals in just eight minutes.

Van Persie then watched his side concede a further four goals in the final 20 minutes to give AZ Alkmaar their record win in the Eredivisie, moving them up to second place in the table.

It was also the first time Heerenveen had conceded nine goals in the league and leaves them 12th in the table, with four points from Van Persie's first four games in charge.

"This is part of football. I have not been traumatised by this and neither have my players," said Van Persie.

"Even when things aren't going your way, with three goals in quick succession in the second half, it's important to keep doing the things you agreed on.

"We'll keep playing our own game. That's what I believe in and what we believe in."