The two sides played out a pulsating 2-2 draw at the Etihad on Sunday, which kept City a point ahead of the Reds at the top of the league table.
However, there were a few questionable calls along the way which could've otherwise changed the course of the thrilling encounter.
Hackett notes three instances where Thiago should've been shown a yellow, but was instead booked just once - in the 62nd minute.
He got away with a foul on Gabriel Jesus just five minutes later. After that, he brought down Kevin De Bruyne with five remaining on the clock but somehow won a free-kick for it.
Had the Spaniard been penalized, he would've not only been sent off but also banned from their FA Cup semi-final clash on Saturday.
With Liverpool down to 10 men, the Sky Blues would've had a better chance of winning the match and opening up a four-point lead in the league.
Speaking to Football Insider's Connor Whitley, Hackett analyzed the game, saying:
“It was a magnificent game. In fairness, overall, I think Anthony Taylor officiated well and was a little bit lenient. He was trying to manage it effectively and I think he did."
“The outstanding error that didn’t work in his favour was how he handled Thiago. He makes a first challenge, the player is on the way to goal but it’s worthy of a yellow card. Taylor has applied a risky advantage but play continues forever."
Questioning his decision to let the Liverpool midfielder off the hook for the next challenge, he added:
“He had two things, has he forgotten who the player is? It’s unlikely – when you’re refereeing these teams you know the players. Or, will he lose credibility if he goes back and shows the yellow card? I think he’s decided to wipe the slate clean."
He also said:
“Thiago doesn’t help because he then gets a yellow and we all refer back to the fact he should have walked. There’s no question in the context of the game you don’t want to see players dismissed because the game was always under Taylor’s control. I sympathise with him, he needs a bit of luck in that scenario.
“There is no question Thiago should have been sent off."
Liverpool need Manchester City to drop points
With just seven more games remaining into the season, the title race might go right down to the wire.
Manchester City are leading Liverpool right now, but things can change before the end of the season. Liverpool has a relatively tougher run-in going into the final stretch of the season.
Barring West Ham United and Wolverhampton Wanderers, all of City's fixtures are against teams outside the top 10. The Reds, on the other hand, still have to play Tottenham Hotspur and Manchester United.
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