Each week, an AFL senior coach will write an exclusive column for AFL.com.au in partnership with the AFL Coaches Association. This week, Fremantle's Ross Lyon looks at the role of taggers and run-with players in modern footy.

MY EARLIEST recollection of tagging was in the early '80s when Robert Walls was coaching at Fitzroy. He had Scott Clayton and Leon Harris, who became strong go-with players.

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I also remember Shane Heard, a premiership player at Essendon, who was a tough tagger. He ended up playing state football for Victoria after Kevin Sheedy famously smuggled him in late. That elevated the status of the tagger, and from there, it grew and grew.

In my experiences as an assistant and senior coach, Chris Bond, Freo's football manager, was a tagger at Richmond. In recent history Brett Kirk, a Sydney Swans captain, premiership player and best and fairest was a go-with player. At St Kilda I had Clinton Jones, and here at Fremantle, Ryan Crowley.

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You might have heard the terms 'hard tag' and 'soft tag' before. It's all terminology. A hard tag is a lockdown player. Terry Wallace used Tony Liberatore as a complete lockdown player. Don't worry about getting the ball, just stop them hurting us offensively.

What's really developed over time is the soft tag, or the 'go-with' player, where your tagger tends to work off their player more. You can choose to maybe negate the opposition player in certain parts of the ground. Let him have it in your forward 50, sit there and wait for him to come out and make sure he doesn't get it in midfield, goal-side of you, running forward.

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You might defend the player in one part of the ground with a soft tag, but once it gets in your forward half, you attack them. Cameron Ling was a good exponent of this. He'd go with you, but once his defence got it, he'd break wide to be an outlet.

Then there was double-teaming. Greg Williams was an example of a great ball-winner and great runner, so teams started to double-team him, putting someone different on him in each half. Other scenarios include the 'hot-and-cold', where you put a tagger on the opposition midfielder, and then put an attacking player on him to mix it up.

There's been an evolution of the go-with player over time. When Sharrod Wellingham was at Collingwood, he would negate you but also work off you strongly. Crowley has a great knack of kicking goals for us. He doesn't get a lot of possessions, but he kicked 12 goals last year.

When deciding which opposition player you are going to tag, there are a number of different factors that come into play. You first try and identify what potential weaknesses they might have. If they have a perceived weakness, you might try and exploit that in certain areas of the ground. How instrumental do you think they are to their team's chances of winning and losing?

Other times it might be a case of, you know they're going to get it, but make sure they handball and don't kick. I remember when I was at the Swans in 2005, West Coast's Chris Judd used to get the ball a lot.

In the Grand Final, it was a case of: 'As long as he's handballing we're happy, but if gets out where he can run and kick the ball we're in a bit of trouble.' The only time you wouldn't tag a player is when you decide you're good enough to cope with them getting the ball.

I don't spend a specific amount of time each week planning for a tag. I tend to do it off my bank of knowledge.

I've watched all our opposition play numerous times. We're also very fortunate to have great access to video on our laptops. It builds up your knowledge base, and then you come together at match committee and bang it out. We'll look at things like the numbers and effectiveness of the opposition's midfielders and come to a decision.

Sometimes we won't decide until really late on whom we will tag.

Ryan Crowley will often come up with two or three players that he might tag and then do a lot of research with Brett Kirk. They'll sit down and watch footage and talk about it. Brett's got great experience at helping in that area. There's times when a certain player doesn't suit Ryan, so we might put an outside runner on him and change it up a little bit.

During a game there are a number of different scenarios that may arise. One is what the commentators call the 'ring-around-the-rosy'. For example, an opposition player who is getting targeted by us will go to another one of our players to try to create a two-on-one match-up.

Scoreboard pressure tends to see which team breaks first. How far do I push to get the match-up I want?

There are many decisions that have to be made in the coaching box during a game. If the scenario ever arises when I have to consider changing a tag, I'll always have a look at the big picture. If the tagger is being beaten but the team is going well, we'll stick with it. If he's being beaten and the team is getting smacked, well, what's the point? We'll change it and throw something different at the opposition.

Basically, with any decision in the coaches' box, it's a contingency-based approach. There are no hard and fast rules. It's a bit of gut instinct. We'll gather all the information and make some decisions on the run. I don't have a hard and fast rule on anything. I just assess on the spot and as we go.