McManaman, 21, who was making his first start in the Premier League, got a slight touch of the ball before following through and catching the defender on the knee and thigh.
The game was held up for five minutes while Frenchman Haidara received treatment on the pitch before he was carried off on a stretcher.
Pardew dismayed by "awful" tackle
But Halsey did not award a free-kick for McManaman's tackle on Haidara.
"It was an awful tackle. I have got a boy going to hospital and that's a worse feeling than losing," said Newcastle boss Alan Pardew.
"It looks like knee ligaments and he's got terrible bruising on his leg as well.
"It looked a bad challenge but I didn't realise how bad until it filtered through to us from the sideline."
Pardew's frustration was compounded when Maynor Figueroa appeared to handle in the build-up to Arouna Kone's 90th-minute winner.
"It is almost injustice you feel," Pardew told BBC Sport.
"Your team-mate has got a terrible injury and the tackle is not punished. It's difficult - you want to get that extra bit, not retribution, but you want to win the game."
On Sunday Wigan boss Roberto Martinez said he was confident his striker would not receive a retrospective ban - which would rule him out of their Wembley FA Cup semi-final against Millwall - as a result of television evidence.
Martinez defends McManaman tackle
He said: "It is a contact sport and these things happen but there was never any intent.
"What you need to look at in those incidents is if there is intention, a nastiness about the tackle. We are not a nasty team.
"He [McManaman] has not a nasty bone and is not bad-intentioned.
"When you get the ball and then there is a follow-up it is very difficult for a panel to punish that."
The challenge sparked a half-time fracas with Magpies assistant John Carver trying to get to the Latics forward. Carver was sent off along with Wigan coach Graham Barrow.
"If the opposing player had a bad injury, as a club we will contact the player," added Martinez.
"I can guarantee that it is part of his enthusiasm and trying to fight for every ball. Maybe it's just a striker's tackle.
"I believe it is a bad challenge but it's not malicious."
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