The Belgian scored an equaliser from the penalty spot after Ezequiel Lavezzi had put the hosts in front, as the Blues pressed PSG into surrendering possession during a frantic first half.
|11/4||Chelsea are 11/4 with bet365 to reach the Champions League semi-finals|
"We had the game in our hands in the first half," Hazard told BeIn Sport. "We came back good and we managed the game.
"But the second half was complicated. We were a bit tired and it felt that way towards the end. Now there's a return leg and we will do everything to push [PSG]."
Hazard was left ruing fine margins after his volley struck the woodwork with the game level at 1-1 in the first half.
He added: "If my shot went to the back of the net instead of the post, the game would have been different. We could have done better by playing better on the counter. 3-1 is complicated but we will fight to [progress]".