In this game there are those "special ones" worth keeping... I wind up naming my stadia after the ones I keep whole career.
They need to play almost every match and a extra training to keep up Q. On my no money teams I play 'em every match.
Here's one from a team that I occasionally watch videos for T on and also hasn't always promoted:

Click image for larger version. 

Name:	vv.jpg 
Views:	62 
Size:	52.0 KB 
ID:	42049

And another, he's retiring after this season >sniff<

Click image for larger version. 

Name:	jan.jpg 
Views:	61 
Size:	51.5 KB 
ID:	42050

Mostly players last about five seasons on my teams (excluding BvB where I do a lot of training they stay longer)