Amazingly it was Dietmar Hamann, in a previous FM version (not sure which) for me.
After playing poorly I told him to improve, he was then sent off in his next game and was therefore fined, then on his return (in a cup game as he needs to earn his way back into the true starting XI) he was sent off again.
Started to become a terrible influence in the dressing room until I released him on a free (which was allowed but cost a good few million), it pained me to do it but it was the best decision for all involved.
I very rarely have players that do anything like that, but the worst for some reason has been Bacary Sagna :S
After he played **** in a crucial league game, I gave him a warning. In the next game he got sent off, so I fined him a weeks wages, which he got angry at. I ended up making him rot in the reserves until I could sell him.
Lewandowski was a real pain the **** from Day 1 during my Dortmund save. Even when everyone else was at, or pushing Superb morale thanks to the domestic success we were having, this guy was never more than 'Okay'. Even after conversations with him about his future where he said he'd be okay to wait a couple more seasons to make us a better club, he'd still be whining about something.
Dani Alves, gets red cards constantly then moans when I give him a warning or a fine. Then moans that he's not getting enough games when it's because he's out suspended. Always unhappy about something.
Rafinha on FM12(Bayern Munich RB), always had poor discipline but his performances really made up for it(7.4 AVG across 3 seaons).
On FM13 it has to be between Nainggolan or Wilshere on my Arsenal save. They're always picking up useless yellow and red cards, but again, their performances make up alot for it.