Just before half-time and with the score level at 0-0, Jordan Henderson played Mane through on goal with an accurate long ball – prompting Christensen to wrap his arms around the Senegalese to bring him down.
Referee Paul Tierney initially handed the Dane a yellow card but upgraded the booking to a red after consulting the pitchside monitor.
And Mane – who went on to score both of Liverpool’s goals in the 2-0 win – says he knew Christensen would be sent off after the review and even told him so.
“When he made the foul, I knew that it was a red card because I even told him, my friend, it was a red card,” Mane told Sky Sports after the match.
“Then after, the referee gave him a red card, so it was lucky for us.”
Liverpool made the numbers advantage count early in the second half as Mane headed home from a Roberto Firmino cross in the 50th minute.
Did Christensen need to make the last-ditch challenge on Mane? Have your say here.
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And it did not take long for Mane to add his second goal as he pounced on an error by Chelsea goalkeeper Kepa Arrizabalaga to poke home from close range.
The costly mistake by the Spaniard comes as the Blues are heavily-linked with Rennes shot-stopper Edouard Mendy.
Manager Frank Lampard has grown impatient with Kepa and is searching for a more reliable goalkeeper as he aims to improve on last season’s fourth-place finish.
Chelsea had a chance to pull one goal back as Timo Werner drew a foul from debutant Thiago in the area – but penalty specialist Jorginho saw his effort from 12 yards saved by Alisson.
The result leaves Chelsea with one win and one loss from their opening two Premier League games, while Liverpool have won both of their matches ahead of a clash with Arsenal next Monday.
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