Premier League champions Liverpool were helped by an own goal from Nicolas Tagliafico to get off to a winning start in the Champions League against Ajax.
Jurgen Klopp's injury-hit side, who were without talisman Virgil van Dijk, were tested by Ajax but did enough to leave Amsterdam with a clean sheet.
Tagliafico sliced Sadio Mane's cross into his own net with 10 minutes of the first half remaining, moments after Liverpool keeper Adrian denied Quincy Promes from close range.
Liverpool's Fabinho then acrobatically cleared Dusan Tadic's lob off the line, before Davy Klaassen's powerful effort bounced off the inside of the post in the second half.
The Reds, who also face Atalanta and Midtjylland in Group D, were returning to Europe as English champions for the first time since 1984-85.