Kris Commons and Anthony Stokes will have fitness tests on Wednesday ahead of the game.
Both players suffered ankle injuries in the 1-1 friendly draw with Inter Milan on Saturday.
Scott Brown, Kelvin Wilson, Thomas Rogne, James Forrest and Beram Kayal are back in contention after being left out at the weekend.
HJK Helsinki coach Antti Muurinen insists his players will not be at Celtic Park to make up the numbers.
The Finnish side arrived in Glasgow on Tuesday buoyed by their 9-1 aggregate win over KR Reykjavik in the last round and with 19 league games under their belt but finding themselves as underdogs despite the Hoops looking forward to their first competitive game of the season.
Before his squad trained at Celtic Park, Muurinen was respectful of the Scottish champions but bullish in his attitude.
Speaking through an interpreter he said: "I told the players that we didn't come all the way here to be afraid, 95% our time should be spent talking about how we play and five per cent about the way they play.
"There is no point in being in sport if you don't believe in victory.
"Of course we recognise that Celtic are a very strong, powerful team but we have to believe that we have a chance to win, even if there is a great imbalance between the teams.
"It will be an exciting experience for us.
"We are not expecting any surprises from Celtic, their tactics will be to crush us which the fans expect.
"So I can expect the first 15 to 20 minutes to be the most important part of the game."
Muurinen, who admitted he would be happy if Georgios Samaras was left out of Lennon's starting XI, believes his side's superior match fitness "could be a factor" over the two games.
He added: "What could be an advantage is that we are well into our season, we have been playing games for months and Celtic are still in pre-season.
"As I understand Celtic Park can take 60,000 and that will obviously bring a lot of heat on my players but I want to believe in my players.
"And we don't have the same have-to-win pressure on us as the home team, although people back home are waiting on lots of things from this game."
Celtic (from): Forster, Matthews, Lustig, Rogne, Wilson, Mulgrew, Izaguirre, Brown, Commons, Kayal, Ledley, Wanyama, Forrest, Stokes, Hooper, McCourt, McGeouch, Twardzik, Samaras, Zaluska, Bangura.