John Obi Mikel admits he let himself down early into his Chelsea career.
The Nigeria midfielder has kicked off the season in impressive style.
"It doesn't feel like I am in my fifth year," he told chelseafc.com. "I was 18 when I came, I had a bad start, it was a wake-up call to me, and I got sent off a couple of times and booked a lot, but now I am happy and I feel I am still getting better, I win the ball more now without fouling people.
"I do think I am more disciplined when I play. Playing for Chelsea you always have the full-backs going forward, Ashley Cole plays like a winger so I am the one who keeps the balance of the team and it is something I learned to do. It is a sacrifice I have to make for the team, not going forward and getting the goals."
