NEIL Harris claimed Preston should have had a player sent off and that Lee Gregory was wrongly flagged offside before scoring as Millwall were pegged back at The Den.
The Lions went in front through Aiden O'Brien's fourth goal of the season, before Gregory found the net with 17 minutes left only for the linesman's flag to go up.
And Millwall were denied the win when Callum Robinson levelled with 10 minutes left.
Harris felt that Preston midfielder Ben Pearson should have been sent off after taking down Jed Wallace, following an earlier booking for dissent.
"I thought there were two very fine calls today, both that should have gone in our favour," Harris said. "Young Ben Pearson should have been sent off because it's identical to Jake Cooper's second yellow card at Sheffield Wednesday, if you want to look back on YouTube or whatever. It's an identical decision, there is cover around the ball but he's stopped the player progressing up the pitch. So I don't understand that one.
"The second one, Lee Gregory scores through one-on-one and he's clearly three yards onside. I've watched it back from two different angles on both our cameras and he's clearly onside. Two fine-margin decisions at 1-0 can affect the outcome of the game. They went against us today."
The point moved Millwall seven clear of the bottom three.
"It's a good point," Harris continued. "When you're 1-0 up at home at half-time you're disappointed not to get three, naturally.
"Against a good side, a competitive and aggressive side with the way they play, a team that are going to be in and around the top six come the end of the season, all in all it's a good point.
"It was very similar to up at their place, two teams that work very hard, you're not going to find more hard-working teams in the division than Millwall and Preston.
"I've was very public before the game about my admiration for how they play and what they do as a club. They're a good model for teams that come out of League One to follow. They're got some good young players and we had to be at our best today.
"At times without the ball we were very good, we limited them to very few opportunities to even get in our box. There were a couple of shots in the first half from distance, couple in the second, and the one time we gave them space was the goal. That's frustrating for me but we'll certainly learn from that."
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