Ben Smith mentioned on Twitter that City are prepared to bid £18 million for Agger.
I was afraid something like this would happen 
I thought they'd already bid £18M and that had been rejected. My worry is that despite all the indications being that Agger wants to stay and sign a new contract that FSG are looking at his age at the end of his contract and seeing no re-sale value, plus his injury situation, and if a bid of £20M+ comes in then it will be accepted.
Now it's one thing not want to pay a transfer fee for a player who'll have no sell on value at the end of his contract, but not issuing a contract renewal to a player who is 27, who has already more than repaid his original transfer fee because in 4/5 years time he'll have no re-sale fee is just madness. If you buy them young, get the best years out of them and at the age of 31/32 you either offer them a year at a time if they've still got something to offer or you let them go on a free and thank them for their contribution, you should be satisfied.
In essence the only players you should ever be selling are ones that have come through the academy and proved by the age of 21-23 not to be good enough.
Any player you buy you should hardly ever sell because you will want them until they reach the stage where they've peaked and are just at the very early stage of starting to come down the other side of the peak. That also takes into account the player possibly being upgraded once aswell. That's of course if you've not made a mistake of some sort with the signing. Ideal world, I know.
Wenger's known for being reluctant to offer a new contract to a player 30 or over. A 3 or 4 year deal you can understand but sometimes a one or two year deal would see you benefit from the wisdom that comes with experience, the calming influence that can have and the knowledge can avoid being caught out by any physical lessening.
If you know your players and time their contracts to their likely phsical state at thirty plus, by the time your player's contract is up at 30/31/32 etc you will have had the absolute best out of them whilst leaving them just attractive enough to another club for a free or nominal fee but without that club getting anything that still could have been of benefit to us.