Furious Stevenage boss Steve Evans claimed Lincoln should have had a man sent off during their dour goalless draw.
Evans, who was himself booked for remonstrating against a decision in the first half, was adamant Ethan Erhahon should have received a second yellow card for a foul on Louis Thompson with 20 minutes to go.
He said: “For me there’s a massive, massive, pivotal moment in the game.
“I don’t want players sent off, but the referee will justify why he doesn’t give a second yellow for a free-kick when Louis bursts towards the box.
“It’s just a bad decision from a referee who I thought got around the pitch, was strong about his opinions but gave me a yellow card for lifting my arms.
“Michael’s (Lincoln boss Michael Skubala) running around waving his arms when Jamie Reid collides with the goalie and he just gets a smile.
“Bobby Madley talks well. I’ll give him compliments for being a strong referee, but you have to be able to come to Sincil Bank and give a second yellow.”
After seeing his side miss the chance to go five points clear of seventh-placed Oxford in the play-off race, Evans added: “It was two teams that knew it was important not to lose and there was a lot of cancelling out.
“I don’t remember our goalkeeper making a save and I know theirs didn’t. There was a lot of industry. They put in a shift.”
Lincoln stretched their impressive unbeaten run to 10 matches and have kept four clean sheets in a row.
Skubala said: “It wasn’t a nice game of football. That’s a Steve Evans team, you know what you’re going to get.
“I thought we dealt with it really well. In the end we were happy not to lose.
“It shows how far this group has come. We’re really disappointed we didn’t win the game. I told the lads not to worry because they’ve come a long way.
“When you play a Steve Evans side and a Stevenage team and you’re disappointed not to win, you’re doing a good thing.
“There was a lot of aerial. Our back line stood up well, their back line stood up well.
“I think in the end it was more in the air than on the floor.
“I thought it was a good test. When we went to their place I thought we got bullied a little bit and that didn’t happen today.
“If we’re disappointed not to win that, it shows how well we’re doing at the moment.”