Darwin Nunez stars as Liverpool beat spirited Hammers
West Ham - or, rather, Alisson Becker - gave Liverpool a couple of scares early on, capitalising on errors by the goalkeeper.
The Brazilian misplaced a couple of simple passes, inviting pressure from the opposition attackers at the Kop end in the opening 10 minutes.
But the Reds shortly settled into the game and began to dictate the pace.
Darwin Nunez made good on the early dominance enjoyed by Liverpool, converting a sublime cross by Kostas Tsimikas in the 22nd minute with a cool header.
The Uruguay striker smashed an effort off Lukasz Fabianski's near post in the 39th minute, almost rounding off an impressive first-half performance with a brace.
A couple of moments later, VAR controversy would rear its head as it was ruled Joe Gomez had fouled Manuel Lanzini just inside the box and West Ham were awarded a penalty.
Jarod Bowen failed to convert the spot-kick as Alisson called the England man's bluff and pushed out the effort to maintain his side's lead at the break.
West Ham, visibly frustrated with how the first-half ended, had an extra 10% in the tank and pressed Liverpool early on in the second period.
Jurgen Klopp opted for a triple change just before the hour mark, summoning Fabinho, Curtis Jones and Harvey Elliott from the bench, replacing Nunez, Thiago and Fabio Carvalho.
Noticing cracks in Liverpool's armour, the Hammers continued to push the hosts into the final 30 minutes and made a change of their own, swapping Pablo Fornals for Said Benrahma.
Roberto Firmino, seemingly becoming Liverpool's focal point after Nunez was withdrawn, was denied two big chances to make it 2-0 in succession.
Klopp's changes did anything but help his team on the night, though, as West Ham managed to carve out more chances than the home side and looked more likely to score, coming close a few times.
But Liverpool were able to hold their own and ushered out the result at 1-0, perhaps feeling relieved at the sound of the final whistle.
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