The Merseyside outfit made a brilliant start to their Champions League opener after Daniel Sturridge broke the deadlock with a powerful header in the 30th minute.
Liverpool FC doubled their advantage when James Milner scored his second goal of the season from the penalty spot after Georginio Wijnaldum was fouled inside the area.
However, PSG halved the deficit before half-time when Andy Robertson failed to complete a clearance and Thomas Meunier scored against the run of play to offer the visitors hope.
Sadio Mane had a goal ruled out in the second half before World Cup winner Kylian Mbappe levelled in the 84th minute after Mohamed Salah carelessly squandered possession.
Firmino, who sustained an eye injury during Liverpool FC’s 2-1 win at Tottenham Hotspur last weekend, came off the bench to score a dramatic winner in the second minute of added time.
Former Tottenham striker Lineker took to Twitter to lavish praise on Firmino for his decisive goal.
Lineker wrote on Twitter: “Special and deserved winner for @LFC from Firmino. 👏👏”
Liverpool FC will take on Southampton in the Premier League this weekend.
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