Lennon's side enjoyed their first Champions League success of the season with a 2-1 win over Ajax on Wednesday, but they have a number of injury doubts for the Scottish Premiership clash at Firhill.
James Forrest (ankle), Charlie Mulgrew (heel), Beram Kayal (thigh) and Mikael Lustig (hip) are all facing fitness tests, while Derk Boerrigter, Kris Commons, Adam Matthews and Steven Mouyokolo remain sidelined.
But with the fixture at Partick moved to Sunday, Lennon has a crucial extra day to assess his walking wounded after a hectic start to the season.
"It is just a huge volume of games and it has been for quite a while," said Lennon.
"It was just a short break in the summer. We came back early and we were playing (Champions League) qualifiers in mid-July and I know I sound like a broken down record, but this Thistle game is the 20th competitive game already and that's quite a start to any season.
"It is a great help having the game on the Sunday because it gives us that extra day for the players to get that recovery in and training has been quite light.
"But off the back of a brilliant win, the players will be really looking forward to the game."
Meanwhile, Hoops defender Virgil van Dijk has dismissed claims from Holland that Celtic were fortunate to take all three points against Ajax at Parkhead.
"Everybody thought that Ajax were the better side and we won with luck but I think we deserved the win," he said.
"Although we didn't create a lot of chances, you could see and feel that Ajax wouldn't score a goal until they got one in the last minute.
"They had a lot of the ball and we knew that before the game. But a lot of ball possession doesn't win games and that's what you saw on Tuesday.
"If we get a result in Amsterdam (in the return game) we have a good chance of going to the next round, but Sunday is the next game that is coming and we will focus on that first."