The German coach praised his side for an efficient performance, but rued Franck Ribery picking up an injury, which he claims is just a "small muscular problem"
A solitary goal by Thomas Muller, from the penalty spot, was enough for a vital three points for the Munich giants, who are now equal on points with Valencia and BATE Borisov in Group F.
"The Champions League is a different competition to that of the Bundesliga," admitted Heynckes, speaking to reporters after the match.
"We did not play well in recent weeks but we did the job against a good Lille side, who had a day off and more. There were few opportunities for both sides.
"At half time, I had to substitute Franck Ribery, who had a small muscular problem. And it is difficult to manage without such a player.
"We showed that our team has great experience at European level. With this victory, we have increased our chance of qualifying. 1-0, it's still a tight score. Anything can happen but Lille had few chances, the credit goes to my defence," he reasoned.
Ribery believes that the result was vital for Bayern's Champions League hopes, and explained his thigh problem.
"It was important to win. It was not the best match, but it was well controlled until the end. It's good for the confidence. Lille are a good team, well organised, but they have lost a lot of players.
"I felt like a cramp in the acceleration. It was difficult after that, because it disturbed me. I didn't feel 100 per cent. I talked with the doctors and they told me it was nothing serious, but there was no reason to take the risk.
"I'm going to get some rest and hopefully, I will play this weekend," he said.