Lennon's team go into the match as underdogs with Celtic arriving at St Mirren Park undefeated in 23 league games and seeking a ninth successive Scottish Premiership victory.
St Mirren are hoping to bounce back from Thursday's 2-1 defeat against Kilmarnock.
But the Buddies manager believes his side have a chance if they show the same belief that led to them knocking Celtic out of last season's League Cup at Hampden.
"We showed last year in the League Cup semi-final that we can compete with Celtic and we can beat them," Lennon said.
"If you want to beat the best then you need to know what their strengths are. We certainly know they have strength all over the pitch.
"But what we have to do is make sure we are 100 per cent focused right throughout. We didn't do that on Thursday and we were punished.
"It was very frustrating for us because I felt we deserved more for our efforts. We put a lot into that game but suffered from one mistake.
"We know Celtic have that type of quality all over the pitch, so we need everyone to be focused for the full 90 minutes plus."