Rangers extended their lead the top of the league table to 19 points with a 1-0 win over Celtic in the Glasgow derby at Ibrox on Saturday, but the Bhoys do still have three games in hand.
Lennon’s future at Celtic was under the scanner last month, but he led the side to a turnaround in form and McManus admits the Bhoys were the better side at Ibrox on the day.
The former Hibs man insists Lennon did pick the team that most Celtic fans wanted to see in the derby, deploying Ismaila Soro and David Turnbull.
But McManus is clear that the result is the most important thing and it leaves Celtic in a bad spot.
McManus said on PLZ Soccer: “I don’t think you can blame Neil Lennon for the result.
“I think he played a very positive team. He played the team that most Celtic fans wanted.
“He played Ismaila Soro in there, he played Turnbull for energy in the middle of the park. He played two strikers.
“The Celtic fans were delighted when the team came out, it is a team most of them would have picked.
“Celtic were the better team on the day, but the result was everything and Rangers won the game.”
McManus feels Celtic now have a big decision to make over keeping Lennon until the end of the season, as they could bring someone new in now to assess the squad before the summer transfer window.
“It piles even more pressure on Neil Lennon. Is it a situation now that you give him until the end of the season?
“I don’t think if Neil Lennon if he goes until the end of the season will be the manager next season.
“So is he just keeping chair warm for someone else or is it a situation where it’s time to cut ties with Neil and bring someone else with a view to next season?
“With a view to looking at the players Celtic have bought just now and who he wants for next season.
“It’s a big decision for the Celtic board.”
The Celtic board have stuck with Lennon despite coming under tremendous pressure from fans last month.