The French winger was shown a straight red card for a challenge on Baines late in Albion's 2-0 Premier League defeat at Everton.
It was Albion's first red card in 53 games and Knockaert was slammed for the challenge on Match of the Day on Saturday night.
Host Gary Lineker, who scored 48 goals for England, said when watching the incident again: 'An awful tackle by Knockaert, dreadful wasn't it."
Frank Lampard, capped 106 times for England, then said: "There are red cards and then there are red cards and this is a particular one.
"When you do that to a fellow professional, leave the ground two-footed and go through him like that, there's some sort of red mist.
"That's as bad as they come and fortunately he doesn't make the contact that he maybe could have made. It was a really, really bad tackle."
Lineker added: "He could have done a lot of damage with that, it makes you wince just looking at it."
A number of football fans on social media were also quick to criticise Knockaert. The Albion winger was the victim of a horror tackle by Watford's Miguel Britos earlier this season and pundits also condemned that challenge.
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