The Senegal international completed a big-money £30m move to Liverpool from their Premier League rivals Southampton in the summer transfer window.
Mane scored on his Reds debut as the African winger netted Liverpool’s fourth goal in a 4-3 victory over top-four rivals Arsenal at the Emirates Stadium in their Premier League opener.
The 24-year-old has also scored against reigning Premier League champions Leicester City and Hull City in what has been a thrilling start to his career at the 18-time English champions.
Former Arsenal playmaker Merson believes Mane could prove the difference between Liverpool and United in their Premier League clash at Anfield on Monday night.
“Sadio Mane has really impressed me. He’s been quick, sharp and chipped in with goals,” Merson told Sky Sports.
“Sometimes I think he surprises himself with what he does, and that’s not being horrible, so no wonder he catches defenders out.
“He can blow a little hot and cold, but he’s hot more often than cold these days and I think he will be too lively for Manchester United.”
Liverpool are in fourth place and two points behind Pep Guardiola’s Manchester City side, who sit at the top of the Premier League table.
United, meanwhile, are three points adrift of Klopp’s men who occupy the final Champions League qualifying spot.
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