Arsenal fullback Andre Santos admits his defensive weaknesses have been exposed this season.
Those defensive frailties were evident during a difficult first half at Chelsea.
However Santos sparked the second-half turnaround with a 49th-minute equaliser.
"I know I can play well and, if I am here playing for Arsenal, it is because I'm a good player," said Santos to the Daily Express.
"I sat down in the corner of the dressing room at half-time against Chelsea and thought about that. I focused on the fact I must be better.
"I thought about it and decided, 'I have to go back and play much better'. Things have definitely got better for me since then and I am still trying to improve."