The Reds made the breakthrough in the 10th minute when Mohamed Salah finished from close range after Roberto Firmino did brilliantly to seize possession and tee up the Africa forward.
Liverpool FC doubled their lead in the 20th minute when Oxlade-Chamberlain picked up the ball outside the Manchester City area and fired a long-range shot past Ederson to score in successive home games against the Citizens.
Jurgen Klopp’s men polished off a commanding first-half performance when Sadio Mane nodded Salah’s cross into the net to give the Reds a significant lead ahead of the return leg at The Etihad next week.
Former Chelsea FC star Lampard heaped praise on Oxlade-Chamberlain for his wonderful goal to put Liverpool FC in a strong position.
“A shoutout to James Milner, who puts the pressure on before the goal,” Lampard told BT Sport.
“Ox finds himself in a pretty small space but it’s enough for him because his touch was out of his feet and – bang. His touches have to be bang on and he hits it into the Steven Gerrard corner. It’s a fantastic finish.”
Liverpool FC signed Oxlade-Chamberlain in a £35m deal from Premier League rivals Arsenal in the 2017 summer transfer window.
The Reds are looking to win the Champions League for the first time since 2005 when Liverpool FC came from 3-0 down to beat AC Milan on penalties.
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