In-form striker Craig Davies scored his fifth goal of the season after 67 minutes to settle the outcome of a dour contest.
But new dad Lonergan’s “world class” save from former Trotters loanee Jacob Butterfield early in the second half tipped the contest Bolton’s way.
“The first goal was always going to be crucial and that looked a goal for me,” agreed Lennon. “It was a brilliant save and that’s why I congratulated Andy after the game.”
Huddersfield started the afternoon seven places higher than their Lancashire rivals, leaving boss Chris Powell to rue what might have been but for Lonergan.
Powell said: “”That save was the turning point. It was quite even in stats.
“A similar chance for Bolton goes in and ours hits their keeper. We just have to dust ourselves down and believe we are doing the right things, even though results haven’t gone our way.
“I have a disappointed changing room because we were very much in the game. It’s a game you look to take something from because of the position of both teams.
“We knew Bolton had an uplift in form since Neil came in but we felt comfortable coming here and playing the way we did. The chances were there for us to take something.
“I think a draw would have reflected the whole game.”