Police are optimistic that the crowds for this Saturday's super rugby final will be well behaved.

One person was arrested at the semi-final on Saturday, while two were ejected for minor alcohol and behaviour offences.

However, Canterbury Police Operations Planning Manager Stewart Munro says the crowds are usually well behaved.

"There's a bigger crowd in the city afterwards, but as for the crowd at the game, quite honestly we don't have a lot of problems.

He says that they get the odd idiots, but that most people are just there to watch the rugby.

"It's a good night for everyone."

The Crusaders host the Lions at AMI Stadium, the first Super Rugby final in the city in 10 years.