Claudio Ranieri has praised Vardy and Mahrez for their top performances against Manchester City, that saw the foxes win 4-2.
Leicester have struggled to mirror the form that saw them claim the title last season, but they showed glimpses of that in the home win over City.
Vardy scored a hat trick, with Mahrez having a hand in the opener and assisting the second goal.
“The big champions react at the right moment,” Ranieri told BT Sport.
“When they [Mahrez and Vardy] play well, often we win. Today they made a fantastic performance, a fantastic effort for the team. That’s what I love. We aren’t a big team, but we can do something good when we play together.
“We prepared so well for the match, we know all the triangles they [Manchester City] try to do to [get into] the last third. We closed [them down] very well. Of course, at the end we were a little tired and they scored twice, but the performance was good.”
Ranieri highlighted forthcoming fixtures against Bournemouth and Stoke City as crucial, with the Foxes, languishing in 14th place, seeking to climb away from the wrong end of the table.
“The next matches until Christmas are very important,” he said.
“Because we are in a battle against relegation. And I said ‘in the battle, I need warriors.’ And they showed me what I wanted to see.
“They said ‘we believe in ourselves and this system’. If I started with another system, they don’t recognise our style.
“They spoke a lot after the Porto match, one hour, half an hour with me,” he added, referring to a 5-0 loss in the Champions League on Wednesday.
“They understood my philosophy. And I hope now we can go back to the same level as last season. You can’t win all the matches. But you can fight. This is my philosophy.
“Last season, everything was perfect. Not always can you do perfect. But you [can] work so hard to defend your title.”