1997 mercury 40 HP tracker piston play

[bakeefe4]

I have a 1997 Mercury tracker 40 HP and cylinder 3 has about 1/64 or smaller downward play on the down stroke. What is this and should I replace the wrist bearing and or rebuild the motor, or is this OK and is nothing to worry about for now and just keep an eye on it. There is not excessive smoke nor lack of compression on an cylinders. Motor runs fine except for a slight ping noise not a knock and not a tick
I pulled the plugs and that is how I know that there is play in that cylinder

 

[Faztbullet]

2 or 3 cylinder?

 

[bakeefe4]

It is a 4 cylinder