Optimal query

I have 2 tables

1) CLIENTS (ID int IDENTITY, NAME varchar(250)
2) CLIENT_LOG( CLIENT_ID INT, DATE datetime )

Every time the client is selected in the system a row is put into the client_log.

Now i need to create a view showing the last 30 clients selected.

I currently use: select top 30 c.id, c.name from clients c join client_log l on l.client_id = c.id  order by l.date desc

Only problem this is giving duplications if a client has been slected more than once in the last 30.

There are millions of records in each table so I need something pretty fast.

Thanks

Jonas