HAWTHORN forward Cyril Rioli averages just 16 possessions per game. 

But it's what he does when he has the ball, and the pressure he applies when he doesn't have it, that makes him such a valuable player.

Now the 23-year-old's standing in the game has been confirmed by the Official AFL Player Ratings, brought to you by Vero, in which Rioli sat at No. 5 after round four.

Champion Data's statistics show that although Rioli has won 25 or more disposals only three times since the start of the 2011 season, he has kicked at least one goal in all but eight of his past 47 matches. And in those eight games he was far from quiet, averaging two score assists, 7.4 tackles and 3.6 inside 50s per game.

Rioli ranks 21st in the competition for total kicks since the start of 2011 and has the second-best kicking efficiency of the top-80.

He also ranks No.1 for score assists and 18th overall for total goals, and his shot at goal accuracy of 59.3 per cent is among the highest in the competition.

"If he does pick the ball up he makes something happen, and generally it's a pretty big result," Richmond midfielder Trent Cotchin told AFL.com.au.

The Official AFL Player Ratings will be launched on Thursday, May 9.

The ratings are the result of the most sophisticated, detailed and wide-ranging statistical system ever devised for AFL footy. Official AFL Player ratings will allow fans to determine where more than 650 listed players rank against each other.

A player's most recent 40 matches are used in the calculation of his rating.

If you are keen to find out exactly how the ratings work, you can read the initial FAQ here.

In the meantime, we are counting down to launch with a series of exclusive videos in which the top-rated players are discussed and analysed by those with a unique insight into their genius – their opponents.

Last Monday Carlton midfielder Chris Judd was revealed as No. 10, then on Tuesday Sydney Swans dynamo Josh Kennedy was unveiled as No. 9.

Blues skipper Marc Murphy was next up at No. 8, then Lance Franklin was No. 7 and Jobe Watson was No. 6.

Rioli is No.5.

"I think the real bonus to Cyril's game is his defensive work," Geelong star Steve Johnson said. 

"If you know Cyril's within 10 or 15m, you know you're going to have to get rid of the ball a second earlier than you normally would."

"I would say he's the toughest opponent I've ever had to play on," Melbourne co-captain Jack Grimes added. 

"Even though he might not be right there it feels like he is all the time. Because of his run-down tackles he's always in the back of your head."

Make sure you log onto AFL.com.au on Tuesday to find out which player is No. 4.

* The top 10 that we are counting down in the lead-up to the launch of the Official AFL Player Ratings, brought to you by Vero, is how it stood after round four of this season.